My favorite has always been the Boss Turbo Overdrive OD2. Many folks say that it is without character but the pedal is what you put in to it. My feeling is that, you, the player making it do 'it's stuff'. So, the pedal reacts to the dynamic you put in. My suggestion is to have it in line with an EQ and a tish of compression. By itself, it can sound a bit flabby but if you tweak the tone and tighten it up a tish it becomes a monster.

I'd mentioned about my Frankenstein rig before back in the 80's but it was this:

Kramer Baretta w/ EMG 89 >> BOSS OD2 >> Crybaby (full treb setting) >> 70's era Peavy Classic SS/Tube hybrid >> 4x10 generic cab

Very odd rig, I know but it was capable of massive, tight overdriven tone. Call it the sum of junkpile parts but it worked very well.

The point is that at the heart of all that was the OD2 and getting a little compression and ad hoc EQ from the Wah. The other stuff by itself sounded horrible but with all the pieces, it was a little hard to believe it sounded like it did.

The OD2 provides a good backdrop in a chain that allows you to use another tool or two to harness abilities. I found it reactive to my playing but would not make tone for me, it represented my playing versus 'made my sound' for me.

My two cents...