Peregrine:
You don't indicate where you live, but unless you are in a large metro area with at least several top-notch FM stations, don't spend a bunch of money on a tuner. The overall programming and broadcast quality for FM has declined steadily for years, and there aren't more than a dozen metro areas in the country with FM stations that are good enough to merit a high-quality tuner. Infact, you might be best advised to consider getting one of the new digital radio satellite services, which cost around $12 a month. They have a much wider range of music choices, and the reception quality and content is superior to the FM stations in 95% of the country.
If you are going to buy a used FM tuner, you should consider some of the better analog tuners that were made in the late 1980's. Some of the Sansui and Pioneer analog tuners were quite good, as were the lower-cost Tandbergs. Most of the digitally-synthesized tuners within your budget built between 1990 and today have pretty similar performance specs. The NAD tuners are respectable, as are Adcom, Proton, and NEC (the NEC T-6E and T-6F were really excellent tuners for the money, but they are hard to find on the used market).
