Promise 3.3 drivers seem to work over all Promise 20230 and Promise 20630 controllers, regardless of the vendor.
The main difference is that Promise 20230 controllers only work with the /D# switch (aka PIO) . There are /DA and /M# modes as well (PIO /w ioready and DMA), but those only work with the Promise 20630 controllers, and the success there can be drive dependent.
My experience so far is that a decent storage device on the promise controllers gets about 2.7MB/s without a driver, can get a little better than 6MB/s with "/D8", the fastest PIO, and gets the same with "/DA", PIO with IOREADY, but the same device can get close to 12MB/s with "/M8", the fastest DMA. So that's a significant synthetic boost. I'll do real world tests later.
The "Promise EIDE2300 Drivers v3.3" package comes with a tool to help you identify the fastest settings for your storage device.
Curiously, I have an msata drive on a pata sled that gets about 7.5MB/s with /D8 (fastest PIO) on Promise 20230 controllers, but the system gets unhappy if I attach it via to a Promise 20630 controller. I can get it to post if I remove it from the MR-BIOS drive table and attach the DTC LBA bios, but the drive isn't usable. Running into compatibility issues in many places. I need to get disciplined about documenting them and documenting the remediation steps if I find any. I've had issues with some CFs, some SD's, some old legacy drives, and with Msata devices.