http://www.stopngo.com looks good to me as well. The construction of their plugs makes far better sense than your average rope plug - it's actually mushroom shaped, and they use a nice process for inserting it from the outside and then drawing it back out a little so the mushroom on the inside seats against the edges of the hole. So it's an actual plug, not just something shoved into the hole from the outside.
Having a plugging kit with you when you go longer distances makes a lot of sense, as well as having one at home so you can get the bike to the shop if need be.That way you're not stranded just because of a flat. Need some CO2 canisters or a tiny compressor too of course.
A plugged tire should be considered to have one speed trating level lower than an undamaged one though. Personally, I too would change the tire and only use the plug as a temporary measure, but lots of people ride on with plugs and survive...