I RMA'd an Iwill XP333 version 1.0 last month, because of a bios chip that was bad. (I have 2 of these boards)
I just picked up the replacement this morning. A brand spanking new version 2.1.
The 2.1 will give me a 2.035 Vcore.(1.85, and a +10% setting),and has a few refinements that I'm not too sure about...I've heard a capacitor or two was added.
Either way, I'm impressed. I bought a board, they released a couple revisions since(2.0 and 2.1), and they didn't hesitate to send me the newest version. I've been happy with Iwill for it's stability and performance...now they just added customer support to that list.