This is surely not the advice you may be looking for but I am set up with 2 SSD drives to run Cubase 7. My win7 OS runs on SSD c: drive thru the 6gb SATA connection on the motherboard. My system has 2 other drives for data one is 1tb and two others are 500gb each. My C7 and a few content sets run off another 60gb SSD thru another 6gb SATA . It has been set up for about 2 months and so far works well.
It takes a bit of effort to keep some some software from defaulting to the c drive for installation as what was using about 30 gb initially has swell to near 52gb . Again no issues so far