USBTinyISP reliability

Does anyone use a "real" USBTiny and, if so, with what degree of success?

I made one like this and it's hit and miss as far as being able to upload programs correctly to my AVR (verification errors almost every other upload).

So I am wondering if it's mine or if even the factory ones suffer from reliability issues, as some googling seemed to suggest. Logic tells me it's mine, but I did take all necessary precautions while building it, afaik.

I have adafruit's. It works, consistently - no complaints. However, its form is nothing like yours.

http://www.adafruit.com/products/46

I bought a clone, usbtiny 2.0, 3 years ago. Never fails when uploading or burning fuses. Mine is nothing like yours, mine is based on attiny2313.

Thanks guys, it seems that I have to start looking at mineā€¦