is the Maestro bassoon brand any good? I found one for $1300. If it's terrible, what about the bassoon makes it terrible to play on?

I believe these bassoons are Chinese-made. I have no personal experience with this particular one, but in general I have heard complaints about Chinese-made bassoons. Some of these are: posts loosening in the wood, causing movement or loss of the keys; plating being very thin and wearing off quite soon; inferior wood being used in the bores.

DO NOT buy it unless you can get it for a trial period first. Some Chinese bassoons are ok, but most of them are really bad. I tried to at a very reputable store last winter, and one did not work properly while the other could not even be assembled. (The whisper key pad holder was blocking the bocal socket. Yes, the lock was off.) If they do not offer an iron-clad money-back guarantee, walk away.