I've been using the NS-2 for a few weeks now, just using my noisiest, highest gain pedal in it's loop, and have been very pleased with it.
For all my lower gain and more delicate playing, my signal doesn't go anywhere near the NS-2, so I guess a lot of the outcome of how successful a noise suppressor will be is in how you implement it, and what your expectations are.
I've certainly found the NS-2 to be no worse than the ISP Decimator I use to own.