As long as everything is listed on the ESXi HCL then I can't see too many issues.
The only suggestion is that as you're using large capacity SATA drives you might want to look at increasing the quantity and RAID6 them if the controller supports that, though as it's for lab use it's probably overkill.
The RAID controller you have selected here is a software-RAID solution. I'd suggest looking into a hardware RAID controller with onboard cache. This can greatly improve reliability and performance.
Finding a compatible RAID controller is pretty critical for getting your ESXi setup running just right. Even in a custom system I've tended to go with the HP P410 SmartArray SAS RAID controller because I know they are compatible with the custom image for ESXi provided by HP. I picked up a P410/512MB with FBWC from Amazon recently for $300 which was a great deal.