I switched from a double boot set up, to reflex 2.0 front & R rear, then to Syndicate & Radar HRT which I like best.
The 1/2 rear in either style were an adjustment. First couple starts I pulled my rear foot right out of it.
I prefer the hrt because it’s simpler - no separate liner, it’s more durable, and I can get my foot back in If I crash. R rear no way I could get that back on in the water. That said they skied the same from my amateur point of view.
My ski partner whose in double boots hated both 1/2 rear set ups on my ski because he lifts his heel at some points and felt he couldn’t get it back down, so to each his own.
One note on the HRT, the front plate curvature doesn’t pair with the syndicate, so I had to grind the front of the plate to snug my rear foot behind the front boot. It was easy to do, just no returning it after that...