Most users are not willing to install the OS 4+ times to try different install methods, run numerous registry tweaks and XP tweaks, BIOS changes for assigning IRQs and disabling various hardware, this too me is the main issue. I knew what the CW stuff was about and what I wanted from it, thus the reason I went the distance, to a potential customer who doesnt know exactly what its all about and is going on a review or blurb from some mag or friend, this is where you find difficulties.
For the amount of money these cards cost, you would hope to have solid performance and just enjoy the wonders of DSP. I have a Powercore and a UAD also, both of those cards installed and work flawless, I have yet to have a single issue with either card, maybe SFP4 could build on stability and ease of integration and that could help pull more people into the platform..
PS. IO think they hurt themselfs by doing away with the XTC series of cards, I have a Lynx card with the 2 other DSP cards and wanted to run CW synths and a few effects since I have comps/verbs already covered, I wanted to use my high end lynx for its great converters, but since there was no XTC cards anymore aside from ebay, I just said screw it, ill go with the CW card and get convertersas needed.
Just my thoughts, as scrambled as they are

Cheers!