I like my NYC Big Muff, although it isn't all that versatile. Don't think about palm muting with it, but for big thick chords you can't go wrong.
Also consider how to power the Muff. It runs on 9V but with reverse polarity and a male input connector, opposite from the usual Boss power supplies. Can be overcome, I had to Macgyver a power supply by chopping a daisy chainer and attaching it to the battery clips.
