Pros - Much faster both upwind and downwind, better in gusts, more "parkable" for racing purposes. Great materials/construction.
Cons - Price. Won't handle extreme light wind like previous generations. Not a freeride kite.
I had my first ride last night, wind was 12-15kts with lulls down to 9 or 10. Swell was 2-3', onshore beach break - not normally the conditions I'd choose for a speed run, but oh well. I'm on 21m Ozone race lines w/the 55cm bar, I keep about 2" of backsheeting in my bar tune. My last 15m was a Joker 5, so my evaluation of the J7 is largely a comparison between the two.
Setup of the J7 was a little slower initially because of the diablo line in the speed system. It's one more thing to have to stare at to make sure it's not twisted some way that you're not seeing. If you disconnect your lines from your kite when you pack down, this is going to add 2-3 minutes to your setup each time. There are also 3 way splices in the smallest bridle lines, which was unfamiliar from the J5, so several times I had to walk back up and double check to make sure they weren't tiny knots in the bridle.
The material is super crunchy and stiff, the kite pre-inflates itself just from the elastic rebound of the LE batons and stiff fabric. There are 2 additional intakes on the LE so inflation is very fast. Getting the kite in the air was no problem, but it's definitely a heavier feeling kite when it's in the sky, it "falls" downward in lulls almost like an inflatable does, which is very different than its lower-aspect antecedent. This took a second to get used to, but because it's a foil kite and not an inflatable, the answer was to backsheet the kite from down overhead and carry it a bit lower in the WW. Other than that minor handling difference, it's pretty standard fare flying it off the beach and body dragging out with a foilboard.
Water start was a bit different, I can usually pull the J5 down in the window then sheet out to pop it forward and yank me up, the J7 didn't like that as much; it wanted to do a proper 11 to 2 dive but felt like it settled into its forward-flying position right away, no major piloting corrections necessary, just trigger the water start and then focus on hydrofoil control. That was a huge change as the older kite needs a bit more direction to get sorted. Upwind speed was an immediately noticeable feature, I could just park the kite and focus on foil control and hiking. I don't usually get a good view of my J5 when riding hard upwind, but the J7 was right in front of my downwind eye - easily 10-15% further forward in the wind window. This forward pull made gust handling noticeably better than the older kite, instead of pulling you downwind into a powered up runaway, this thing pulls you forward so you can pinch the foil up and get a nice solid lift out of the added pressure.
Off the wind, the kite shows its biggest differences from its older sibling. There is more ability to change the shape of the kite based on the more modern design of the bridles, resulting in a few different downwind "modes" that took some getting used to. The J5 has a nice broad reach mode, you can stand very upright with your foil vertical and just gently lean back against the harness, it's the cruising down the beach mode. The J7 doesn't really have this, it wants to take the wind on more of a beam reach. I discovered this during my initial attempts at a touchdown gybe, I nosed the board downwind to slow down a bit and felt the kite really lighten up when I started to switch my feet, you need to keep some speed on through maneuvers with this kite as a result.
The other mode is the heart in your throat, holding your breath, relaxing your bowels downwind zorching fast race mode. I discovered this mode when I got a bit stuck on a wave face surfing downwind. Since it was my first time out with the kite, I wanted to warm up by just doing some long steady laps up and down the beach, but the surf was breaking in an odd way at the distance I like riding, so I spent the first hour kind of just cruising up and down focusing on riding the foil, leaving the kite just parked at 45. I have a new front wing on my foil, I rode it yesterday for the first time as well. About 1/2 way through my second downwinder in the surf, I found myself really stalled out on the back of a wave and needed to power up fast to get out in front of the swell. I sheeted the kite in hard and let the nose of my foil track downwind as the speed started to build. Because of the diablo line, this kite has a deep downwind mode that the J5 simply does not.
The J7 pulls downwind at an angle that reminds me more of riding upwind than downwind. I was riding faster than I've ever ridden and at angles so deep, the kite felt like it was almost flying backwards in the wind window while it continued to accelerate. I wasn't able to find the limit of the acceleration, partly due to the new front wing on my foil, but also because of the chop. This kite easily goes 20% deeper downwind than my Joker 5, it's simply amazing. To accelerate, you just pull the kite way back in the window and lean into your front foot to tension the front lines. Within seconds, the kite starts generating much deeper apparent wind and starts pulling the nose of the board downwind. There were several times when I was on the edge of overfoiling but the kite was so stable that deep in the window that I could just drive right towards it to control my speed and it would respond very predictably. It almost felt like my old Naish Pivot when it was oversheeted, powerful steady pull straight downwind. When you sheet the bar out from the deepest downwind angle, the kite creeps forward slowly at first then starts to accelerate through the wind window as you edge against your front lines and head up to a reach. The way power bleeds off like a horse gradually slowing down from a fast gallop. Far and away the best feature of this kite is the bear-away from hiking hard upwind to going straight downwind. When you pull hard on the bar and let the trim all the way out, the kite creates so much downwind pull that it allows you to lean forward and put a ton of weight toeside you ricochet downwind. The feeling of accelerating from 22mph upwind to 30mph downwind while steering through 160 degrees of heading on the same tack is just phenomenal.
It's a bit slower in the downloop during gybes, but I felt like it was a bit faster overhead in tacks, need to readjust my timing, but overall there was no stability issue during either maneuver when I inevitably fell and had to fly the kite back from the brink of the window. Very well behaved.
I suspect that this kite is positioned in the quiver as the "most conditions" kite. The meters looked like they hit up to 16kts last night, mostly hanging around 13-14 with a lull down to 9. I never feared for the kite falling, but it certainly lost its punch in the lull, in a way the J5 does not. I believe this kite is the heaviest 15m Elf has made, which might explain the loss of deep low end. To borrow from sailing:
18m - Code 0
15m - A1
11m - A2
9m - A3/blade