Choose a board for my knees

Hello

first I introduice myself
Fabien, I am french (sorry for my english) and I am a cable rider
I am a big guy (192 or 6.2 feet and 95 kg or 210 lbs) and intermediate rider

And I have some problems with my knees, like patellar syndrome and some arthrosis

so I would like to change my board (hyperlite franshise 142) to a flex board
what I want is softest langing as possible, and also good press (i think I have to decrease kickers)

I hesitate between several boards
- slingshot reflex 145
- LF flx 142 or deluxe 143
- Ronix phoenix s 142

what do you think about that ?

and I saw also the new LF super trip (143 or 147) which seems to be super flex
is there somebody who tried it ?

Thanks
Fabien