ECC system memory

I’m starting to plan a build for a CUDA workstation, one GPU for now (GTX 285 or Tesla C1060 depending on how much memory we need). I’m going to base it on the ASUS P6T6 WS Revolution. I’m trying to decide whether to use a standard i7 920 and DDR3 or whether the stability of ECC would be worth a switch to a Xeon E55XX. Is there a standing opinion on the value of using ECC main memory in a CUDA workstation?