This one is a bit confusing, as you haven't told us whether you want to just boost the pre amp gain of the distortion/overdrive of your amps, or use the clean channels to run the distortion/overdrive pedal through.
I own a Boss DS-1, which I use a pre amp booster for guitar amps. It can thicken the tone and add some very noticeable compression, and generally can sound a bit mushy on the low end of things, but for soloing it can add that much needed thickness I desire.
The SD-1, will actually cut bass out of your signal path when used as a pre amp boost, so it tightens the sound up for heavy rhythm playing, but perhaps doesn't sound as nice for soloing.
Of course, Boss currently have 13 overdrive/distortion pedals available, but those 2 are well known for their use as good pre amp boosts. Also, the Metal Zone is very popular as well, and can also be used as an effective tone tightener/pre amp boost, and it's useful for many genres and despite it's name is not just useful for metal per se.
If you plan to use the pedals through the clean channels, honestly they will most likely sound like rubbish when used through cheap solid state amps, but perhaps you can try out the Robert Keely mods, to see if that helps.