Guys I need to put together a storage solution for a Vmware lab I'm looking at ISCSI. So far I'm looking at building a Centos box with a Perc 5i raid controller and using LVM with ISCSI Enterprise Target, Freenas,or Nexenta. So I must ask what solution are you guys running in your labs and which ones gave you the bese ISCSI performance?

Sounds like you've got money to send. I take it this is for work. If so don't build your own and buy a setup of HP (for example). They have a few options for VM servers. The nice thing about buying it from HP is that the hardware all works (generally). We run a very large VM cluster at my work. The entire infrastructure is HP.
Also, corporate hardware tends to fail less often (this is only my opinion of course).

You really don't want to build your own setup and then be unable to access your data 3 months down the line because a kernel update didn't play nice with your hardware. Worse yet, you don't want to loose data due to a hardware crash because you bought commercial hardware instead of enterprise stuff.

Again this is my opinion. In my lab we have a small data storage server in the lab (slush space) that is built on parts I got from newegg and old hardware. It hasn't died on us but if if anything goes wrong, we new the risk. Experimental results are all kept on the departmental storage server. That baby's not going down easily.

HTH