Fasttrack is a firewall feature. If you'd like to use this device as a router, you can expect more cpu usage than with devices sold as routers. RouterOS runs on all of them. The whole purpose of fasttrack is to speed firewall up.
If you'd like to use it as a switch, you shouldn't have any problems.
Baltic is fine. I have purchased from them a couple of times three years ago.
There is another not very well known company multilink.us, which is usually cheaper than Baltic. I have purchased from Multilink as well. They charge $219 for CRS310-8G+2S+IN unlike Baltic, but they have RB5009UG+S+IN...
I believe they had this info since the beginning. :)
These guys aren't experts in Supermicro servers. This is why we can get this hardware for such low price. :)
If these guys were experts they'd reset passwords on X10DRH-CT and triple the price.
Your link in the first message is with the SAS3 backplane.
I've got two of them. Both have the SAS3 backplane.
I know you were unlucky and got one with SAS2, but nobody else has complained so far.
Of course, YMMV.