I enjoy my cularis, fly in 50+mph winds with no problems. speeds up to 72mph flat out, recorded with eagle tree seagull system.
It likes to fly at ~24mph or faster. For me with all white I I limit altitude to ~1500-2000ft altitude.
Had mine over 2500up in one thermal and it was a dot for me, long spiral to get down.
When slow (below ~20)and tight turns it stalls a wing quick and takes ~15-20ft to recover.
Use rudder and opposite aileron in tight slow turns and not so bad.
When landing it needs brakes of some kind to slow down and stop otherwise it can go ~400+ft distance at ~1-2 ft off the deck.
My first one I stalled to close to the ground, liked it so much I bought another one.
I went 330W brushless PJS1000 motor, 12-6 folding prop and AUW is 48oz with 3c-2100 lipo.
It does take a few hours of work to get going, but well worth it to me.

Never flown the radian so no comment.