I've been doing research for my conversion, and I've come to some conclusions:

1. Chain tensioners are an ugly kludge that doesn't work the greatest.

2. Chain tensioners are far cheaper than getting new dropouts, a new frame, or one of those fancy eccentric hubs.

You might look at Performance Bike's house brand kit (forte) - it's the same tensioner, but it comes with a 20T cog as well, and is cheaper. Doesn't come with "conical spacers for improved cog stiffness", whatever that means.

One technical note that I've come across repeatedly is to make the chain as short as possible before adding the tensioner. That seems to be the trick for skipping/chain wrap issues - a tensioner won't take up as much slack as a derailleur will, but it will give you a little play.

But then again, tensioners are an ugly kludge.