It is a pity that you claim to understand hardware, since you obviously don't. This applies to you: Go away. Or go play in traffic. Really. Either will do and bring an immediate improvement to this forum.
Thunderbolt, which is typically used on Mac's, is a 'new' connection. Well, 'new' is rather doubtful. since it is based on a PCIe-2.0 4x connection with a 10b/8b encoding protocol, that carries a huge overhead (almost 20%) over PCIe-3.0 that uses the 130b/128b scrambling protocol. Thunderbolt is great for laptops. There is no connection faster than that for laptops. It delivers around twice the transfer rate of eSATA, with 10 Gb/s per channel. Effectively it will deliver up to around maximum 950 MB/s transfer rates with 2 or more modern and very fast SSD's in a (r)aid0 configuration. But that is also the downside of Thunderbolt. Adding more SSD's to the (r)aid0 will not improve performance. It is choked. It is almost the same speed an internal (r)aid0 with only 2 SSD's will deliver as a software raid. Nothing more. Thunderbolt 2 delivers around 1350 MB/s maximum transfer rate. Still significantly slower than a dedicated raid controller can achieve.
from Tweakers Page - External Drives
From Anandtech:
By combining the channels together, Thunderbolt 2 enables two 20Gbps bi-direction channels instead of two sets of 10Gbps channels. There's no overall increase in bandwidth, but the solution is now more capable. Since there's 20Gbps of bandwidth per channel, you can now do 4K video over Thunderbolt. You can also expect to see higher max transfer rates for storage. Whereas most Thunderbolt storage devices top out at 800 - 900MB/s, Thunderbolt 2 should raise that to around 1500MB/s (overhead and PCIe limits will stop you from getting anywhere near the max spec).