They are effective and pretty much live up to the hype - I got all but the silver and they all have their merits. I'd try one of each and sell/return the one(s) that don't work out for you. What I found was certain components worked better with certain outlets and the only way I could find which I preferred was to listen. The characterization is pretty accurate from the way they're described on the website, so if you can't try them you probably know which balance is best for your setup.
FWIW I got the double cryoed from Alan Kafton and I have been told it makes a significant improvement, but haven't been able to compare to the non cryoed.
BTW, I'd do this as a last step to voicing your system once you're pretty well done with all else, i.e. cables, interconnect, conditioning, etc.