Question about multiple arrays in a single storage pool

We purchased a PS4100x a couple of years ago and have it set for RAID6. We've been happy with the performance, but we are running out of storage space. We recently acquired a PS6000e and PS4000xv that we are looking to add to the default storage pool and provide us more storage capacity. I was able to successfully join the PS4000xv to the pool as a RAID10 (performance benefit) and want to join the PS6000e to the pool as a RAID6 (capacity benefit).

I've read several different posts about problems mixing RAID levels and drive types (SAS/SATA) and it negatively impacting SAN performance or outright causing SAN failure. Furthermore, I keep finding reference to issues with prior firmware. Unfortunately, I can't find anything current that will help me through this issue.

My goal is to have the following 3 EqualLogic arrays in the default storage pool:

• PS4100x (10k SAS) RAID6 (approx 15TB)
• PS4000xv (15k SAS) RAID10 (approx 3TB)
• PS6000e (7.2k SATA) RAID6 (approx 11TB)

Any help or guidance would be incredibly appreciated. Thank you!