Just like to throw my information out there:
As a 360 owner, I've only been able to get my hands on the Hori EX2, Hori VF5 EX2, and the Hori SC4 EX2. Between us, we've got 4 different sticks, and here are their stories:
1. Hori SC4 Stick (Dragon). Two months after use, buttons started sticking. Modded it w/ Sanwa buttons & 8 way gate, didn't mess up anything inside. Turns out the logic on the board went bad; B+K would result in a B, and K would be unusable for four or five presses. We're still trying to fix it.
2. Hori VF5 Stick (Knight). A year after use, 2 on the stick stopped working. We opened it up, one of the connecting wires' solder had broken off. Stripped the end, hooked it in, e-taped it, slid the wire solder cover back on. Works again. Modded it w/ Sanwa & 8 way while it was open.
3. Hori EX2 Stick (Gwendolyn). No problems after 6 months, was on a modding spree and we decided to put in Sanwa & 8 way gate. No problems after modding.
4. Hori SC4 Stick (SC). No problems after a month. When we got it, we installed another 8 way, but that's about it.