First, does the tuner have presets and if so, how many?

Three banks of ten presets each. They can be given an ASCII name with the remote, and can be quick-accessed via the number keys on the remote, or selected from the front panel. You can freely mix AM and FM presets together in the same bank, it makes no distinction between the two.

Some have discussed the idea of making it "preset-less". In other words, dump the whole concept of numbered presets and simply make a heirarchical tree of radio stations, in the same way that it handles playlists. I don't think they're planning on actually doing this, but it's an interesting idea.

Second, how good (sensitive) will this tuner be?

I've found it to be comparable to most other aftermarket radios. It's pretty good, and pulls in certain weak stations better than my previous CD player did.

Provided you wire the antenna properly, that is. For instance, VWs and Audis need a special aftermarket adapter to be able to supply power to the antenna amplifier. And some cars have diversity antennas, so you have to choose one of them and wire only that one to the empeg tuner.