Just to be clear.... you're offering 5x H310's for $95? Or is it that you're offering 1x H310 for $95 and, you have a total quantity of five that you're trying to sell?
One thing I can say that differentiates the Dell's is that in some cases they need to be modded to work and/or be flashed in some motherboards. I can't say for sure if that's the case with the IBM's and Supermicro's.
details on the required mod....
http://techmattr.wordpress.com/2013/08/30/sas-hba-crossflashing-or-flashing-to-it-mode/