Maybe 325 being softer, it did not bother you as much. With stiffer boots you need more precise fit.
try some of these pads
http://www.tognar.com/boot-fitting-p...eets-1-8-foam/
http://www.tognar.com/ski-boot-heel-...d-wedges-pair/
http://www.tognar.com/bontex-insole-shims/
I think this place is out of philly
http://www.shredsoles.com/shop/jbar/
You can make your boots fit pretty good as long as you are within 1/2 to 3/4 size.
I find I never get a good fit anyways from boots off the shelf (I have wide toe box and narrow heel).
C or L pads with ankle wrap will help you with heel lift.. and use the shims or insoles if the boots are too big overall (or top of the foot pads if it works with your liner).
It's only couple of bucks and worth a try. Get some double sided tape (not so sticky ones) also so you can try moving the pads around to find the right spot.
Then use the tape it comes with the pads. It takes couple of tries.
I rode the Saber for two days before snow turned crap. It was good. Very damp (I havent ridden any metal board so this was the dampest of all the board i've ridden). Held edge well. Little soft between the binding (hopely i'll lose some weight and it will fix it self). Overall I like it. I just need to find binding to go well with this board. What binding have you tried with it?
http://www.youtube.com/watch?v=tD8LEf_UScs
What board did you end up getting?