I bought Photo Mechanic a couple years ago, at a time when Lightroom was a lot slower than it is now. Photo Mechanic offers immediate full-resolution views of raw files, which makes it quite easy to scroll through and find the best images in your pile. It's pretty handy for wildlife photography, where the keeper rate is less than 10% and the "trophy" rate is usually around 1%. You can flag your keepers in Photo Mechanic, and then when you import them to Lightroom the flags remain in place so you can easily find them. The only catch is that the program costs $150, so you have to be pretty seriously annoyed with the Lightroom delay before investing in it. Right now with Lightroom being a lot faster than it was in earlier versions, I find that I don't even bother using Photo Mechanic much at all. But I have a pretty fast computer which probably helps make LR as fast as possible.