There's a Base bar which goes with el cheapo kites like Ride and Trip
Then there's the Universal bar which comes with a swivel at the V-split instead of metal rings
Then there's the ATV bar which is basically a Universal bar but with the above-the-bar trimmer
All 2012+ bars should have lines of the same length
2011-s and older bars were a high Y-split type - thus the front lines were splitting a lot higher and were a lot shorter than the rear lines
There's also the Shift bar for Torches which I don't know squat about as my interest to anything with more than 4 lines is non-existent, so hopefully somebody else can confirm if it is using the same lines as the other models.
Check out the Naish online shop if you're looking for a new bar:http://naishkites.shptron.com/c/kiteboarding-kites_control-systems
2012 Universal can be picked up for a bargain, yet alone 2011... I'm waiting for the 2014 bars to become available to pick up another 2013-one. It's a bit thinner than the 2012, everything else is the same though.