Raid or internal hard drive?

Hi!
I hope you can help me, i am very new to the RAW-Workflow.
I just worked with the codec of My 5DMkIII and didn't have any problems concerning the file-size and didn't need any RAIDs.
I am going to get the new MacPro and i am searching for a Raid-Solution.
As far as I understood, i will put my whole footage not on the internal hard drive of the Mac, just on the external RAIDs (?).
Am i able to edit the BMCC 2.5k-RAW-files directly from the Raid with Thunderbolt 1?
Since the new MacPro got Thunderbolt 2, i am wondering if this will make a big difference. I am worried that the Thunderbolt 1-connection will be the only limiting factor (concerning speed and performance).
Would it make more sense, to get a big internal hard drive or SSD to put your current project on, and use the RAID just for storage purposes?

I hope that you can help me, I could not find any information elsewhere.

Thanks in advance!
Stefan

BMCC 2.5K runs 5 MB/frame, or 120 MB/s @ 24p. First-generation Thunderbolt can easily push 800 MB/s, so there's no bottleneck there. Really, you'd need a RAID with 6+ HDDs (or 3+ SSDs) to see a significant benefit to Thunderbolt 2 over first-gen Thunderbolt, and that would be total overkill for 2.5K BMCC footage. That said, the Pegasus2 RAID systems are now on sale, and do have Thunderbolt 2. Promise sells a 'bare' version of the R4 (that you could load up with drives yourself) that presents a rather nice value proposition. If you're looking for a 4-bay enclosure with hardware RAID 5 support, this one isn't really much more expensive than the options with only first-get Thunderbolt.

The new Mac Pro doesn't have internal drive bays, just an SSD card. It seems very much designed for a model where you use the internal SSD for OS, apps and maybe render cache, and place large footage, etc. on an external RAID, so I think you're looking in the right direction there.

Thanks for your reply!
I didn't know that the MacPro will just have SSDs i thought there is something like the Fusion Drive on the IMacs.
Is there any difference between the different Raid systems?
Is Pegasus the one to go for or is there no difference compared to the systems from Lacie or WD?

Thanks!
Stefan

One attractive feature of the Pegasus that it gives you the option of RAID 5, which basically means you can format the four drives so that the RAID system has a capacity equal to three of them (so, if you add four 3 TB drives, you'd have 9 TB capacity), but if any one of them happens to fail you don't lose data. This isn't a substitute for good backups, but it's certainly nice to have. That 'bare' R4 also lets you add your own drives, which tends to save money over buying a RAID unit with drives pre-installed.