I'm always on the lookout for a bargain, which means a quality product at a reasonable price -- as they say, not "cheap", but "inexpensive."
Well have I got news for you. Christmas has come early this year.
If you're quick enough and go to https://secure.ntius.com/esdsoft/ntispecial08152005_shadow_v2.asp?xID=885&OID=3066 you can purchase NTI Shadow™ 2 for Windows for only US $0.99 -- that's right, for only 99 cents!
I now have my very own inexpensive copy of Shadow. It has been up and running for a few days, periodically copying critical files onto a separate backup drive. The Windows XP system performance overheads seem negligible.
Therefore I give NTI Shadow 2.0 a rating of "Highly recommended" (and, in fact, would have done so even at the regular full price).
The product launch special offer can't last forever -- the regular price will be US $29.99 -- so part with the 99 cents and get in while the going's good.
UPDATE (08 September 2005): I've been using Shadow for a couple of weeks now, and have found it easy to set up backup tasks as well as running unobtrusively in the background. And here's a review that I just discovered that covers Shadow pretty well.