Each worked without any problems, either during upgrading or operation. Each vendor has a their own software, which has been under development for some time. Seemingly, the software is the only clear advantage over the products, however I found each package to be quite complete. While there aren't any glaring differences between upgrades, there are a few issues that are worth noting. Between the three cards, XLR8 only offers hardware modification.
Some people like to modify their cards, while others simply want to install and forget.
Typically, the hardware settings allow the card to run faster than specified. Unfortunately in these Macs you can't push the upgrades beyond the 10x bus limit. But with the XLR8 jumpers, a user can slow the card down if needed. If their Mac's bus is unable to perform well at 50 MHz, as some may not, the user can slow the XLR8 card down to 466 MHz. To say the least, it would be disappointing to run a 500 MHz upgrade at 466 MHz, but at least for diagnosis, the option is available on the XLR8 card.