Had a Sabre 1 150: flew awesome, hard openings
Have a Sabre 2 150 loaded at 1.61 (yep,that exceeds the warning label, I know)
The Sabre 2: has good,predictable openings (Never on heading but on the other hand I've only had line twists on it 2 times, both on wingsuit jumps)
It has fun flying characteristics and a very good flare. A 90° front riser turn initiated somewhere between 300 and 400 feet results in a nice (not canopypiloting-like) swoop that gets the adrenaline going up a bit on the average weekend jumper. When I try to make a front riser turn more than 90° the riser pressure gets to high and I can't hold it.
This year I also tried a Parachute Systems Volt 150. It flies as fun as a Sabre, did have on-heading openings (even when packed like shit because I'm not used to packing brand new gear) and it had a very good flare (also loaded at 1.61 obviously)
The main difference is that the Volt does not swoop when using front riser input. But if your bones are getting older, and you don't need that little swoop for the added excitement at the end of your jump....I would definitly go with the Volt. I have some buddies using them for wingsuiting all the time.In my opinion that is a good reference for opening consistency :o)