my tc electronic classic sustain + parametric eq works pretty fine as a booster
got it in as partial payment on some tube driven maxon I sold
would never pay US$299 (or even half of it) on a new one, but it's a fine pedal
it's not as effective for sustain matters as an overdrive pedal, though
but works quite well for boosting mids while adding just a little compression
it keeps things transparent and naturally fat
for a tight uncompressed crunch and punch, the best thing I had was a vintage maxon 6 band eq
it was quite noisy, though, but nothing my rocktron hush couldn't handle
in the end, overdrives are always easier to deal with