ok, here is my review on the 3 kites mentioned above.
please note that this is my opinion and some opinions of riders who tested them as well.
Some riders had different opinions, but I will make that clear in the review.
Here some facts: I used an X-Shooter 155 board, my weight is 90 kgs and I used the http://www.kiteproshop.com Kitebar-System 60cm with 300 kg lines (which are directer in flying than normal lines)
I don't mention windspeeds, only "pressure", since it is always depending on your weight and board, so my windspeeds are not accurate for everyone.
Gaastra GXR 16.5
I really enjoyed this kite!
It gave me great lift and had a long hangtime.
The handling is nice, not too much pressure on the bar.
The kite turns fast and you don't notice the 16.5 sqm.
It has a good depower range.
The only negative I noticed is that in light winds it pulls downwind and it is hard to get upwind. Once you can ride out of the fixed loop it goes further to the edge and goes upwind very well.
The kite is built very light and has a lighter construction than the Rhino2 or X2.
The quality is very good and the smallest bladders have a valve which locks the air so you get it real stiff. For getting the air out, you have to squeeze it al the time, which goes fast.
Waterstart was good for this size.
This kite has its sweet spot in medium and stronger pressure, but then it really rocks!
North Rhino2 16.0
In lighter winds it started earlier than the GXR.
Very stable in the air, specially in gusts, slower in its turns than the GXR.
I didn't like the lift, amybe it was me, but didn't see anyone getting high with it, therefore it had a long hangtime, once you got air. It is good for "groundtricks" where you don't boost high.
The restart is about the same as the GXR.
The construction is very solid, similar to the X2.
One think I didn't like: the last 2 bladders had this valve like the GXR where you have to squeeze it all the time to get the air out. The last would have been enough.
good kite for light winds and ground tricks.
depower range not as big as the GXR, so in stronger winds you get overpowered faster.
North Rhino2 12.0
the whole performance is like an X2 12.0.
Construction and quality about the same as the X2 12.
Now I can't say better than the X2, but at least same performance.
Great lift and hangtime.
Real quick in turns and offers constant pull which is great for transitions.
Relaunch no problem.
a hot kite for 2003, I liked everything very much.
Now you can find other comments about above kites:
everyone same opinion
Rhino2 16.0 vs GXR 16.5:
some preferred the Rhino2 some the GXR.
But we all came to the conclusion that the GXR pulls downwind in light winds, while the Rhino2 still goes upwind.
The majority liked the lift and movability of the GXR than the Rhino2.