Any kite with a flat profile will give you longer hangtime, like the Ozone Edge for example. The problem with foil type kites is that they move very slowly and as a result it makes it harder to gain height in your jump. But they do provide better hangtime in general...if you can get the height
Biggest jumps I've done including hang time has been on a fly surfer psychos 4. But was average overall man. Haven't been fully lit on the edge yet though, we will see.
I haven't flown the flexi. but i have flysurfer speed 3 15m dlx, 13m edge
If i want glide this is the speed is kite i reach for. it out glides my edge by a factor of 2-1. It truely has insane paraglider like glide.
But apart from the most insane upwind and glide it is **** for most other kitesurfing. I mainly used it on my landboard jumping boulders on the beach. Its the only kite i feel truely safe with height above land. the landings are so... pillowy soft.
Today was 10-12 knots and no others were out. but i was busting backrolls board grabs and jumping boulders on the landboard... whoot.
Ps You can get higher on other kites for sure. but you certainly can't out glide the flysurfer.