Originally Posted by cyccommute
I'm not a fan of seatpost racks either. The ones I've tried ride too high and make the bike handle funny. Plus they look goofy. Before you go down that route, how short are the rack stays on your old rack? You can sometimes get new ones from a bike shop. I've even had some that were made specifically for adding on to the length of the existing rack stays by simply bolting on to the existing stays. You could also get more length by just going to one bolt for attaching the flat part of the stay to the rack (that alone will get you about an inch of length). It makes is marginally weaker but as long as you are only using light loads it should be fine.
The Topeak makes their post-rack with three different angled brackets to mount them at different heights. The V bracket mounts mine pretty low to the tire. As far as goofy-looking; that's the story of my life, I'm afraid. A rack on my bike isn't going to help that either way, so I go for functionality instead.
I wouldn't tour with the thing but for a lunch and a few small items it works great. For me it's an easy way to get a rack on a bike that has no provision for it otherwise.