APEX was real good IMHO. I switched just to give this a try and still have my back-up of ApeX, but I am loving this ROM. I have it OC'd to the same settings on ApeX and I am getting one soft reboot about every 24 hours just like I was on ApeX, so I think the soft reboot issue has to do with the OC and not the ROM itself. However this thing is lightning fast so I really do not want to take off the OC. I am getting scores OC'd just slightly higher with Rubix than with ApeX. Rubix has been 1690 to 1710 on average and ApeX was 1620 to 1640.
I got my keyboard that I loved on ApeX last night so I am in a real good place with this ROM as well. However with either I don't think you can go wrong.