The system I have run this plug-in on is a Pro Tools HD based system that runs with an Apple G5 computer and a Digidesign 192 I/O interface. While I can't say that I'm able to run endless amounts of channel strips within a single session, you do get the option of using each section of the channel strip as its own plug-in, which takes up a lot less processing power and is the way that I usually go with this plug-in. Since this runs in tandem with the card, all of the processing power is taken off of the computer, which puts a lot less stress on all of your sessions. Anyone running this plug-in is running it with the card, so no one should be having too many problems in terms of performance with this plug-in.
I've been using Universal Audio CS-1 for about a year and I can't say I have any complaints about this plug-in. In general I'm a big fan of the UAD cards and the plug-ins that can be run with them as they save processing and sound great. This is a versatile channel strip with a lot to offer both home and professional studio owners. The total price of this plug-in along with a UAD card is pretty reasonable, and definitely worth it for those looking to build upon their plug-in collection with Universal Audio plug-ins and want to save processing power. This does come free with a number of the cards if not all of them, and the entire package is overall a great investment for any studio.