I have tried both and I definitely prefer a slower blade with faster rubber. This also gives a bigger spectrum from slow to fast.
Cheers
L-zr
A couple comments:
1) I do not recommend ALL or ALL+ blade even for beginner. I think OFF- is good (but not OFF or OFF + either). With a good OFF- blade, you can then slowly upgrade the rubber to faster tensor rubber and/or thicker sponge over time. I would basically recommend a good solid 5-ply OFF- blade to start off with.
2) To learn how to engage the sponge, I have heard people saying that at the very mininum start with 2mm sponge. No need to go for max sponge yet. But avoid 1.5mm, 1.7mm or even 1.8mm.
3) Therefore what that means is, not too fast of a blade to start with (but not too slow either). Not too fast of rubber to start with (but not too slow or too thin of a rubber either, unless you have decided to be a defender/choppere and use 1.5mm sponge on the forehand side already).
4) Rakza 7 soft is already pretty good. Not a fast tensor like Tenergy. So if you have trouble with service return, this might be a technique issue. Rakza 7 is like the new Mark V. Good well around rubber.
I agree with the other poster that you should flip the paddle over and see if you like slower, hard-sponge chinese rubber on the backhand side too. If you do like that, the choices are literally limitless.