I went to the Liverpool Guitar Show yesterday with "MJW" Martin, and it was one of the better shows of recent times. A few pieces of vintage gear there, which was a nice change, but we weren't entirely convinced they were genuine. Nice to see "Roland_Rat" there too, hope you enjoy the Rothwell Compressor matey!
Anyhow, I digress...
I was on the lookout for interesting pedals as my amp/guitar rig is sorted. Unfortunately, there was hardly anything decent on show which was a shame. On one stand though, my eye spotted an MXR Distortion III:

It was a little beaten up, and had an incorrect tone knob replacement, and was on sale at £49. As I like to try different overdrive/distortion pedals I offered him £40 and the deal was done. I thought it might be OK to boost my amp for solos when practicing at home.
I totally underestimated this little beauty!
The name and looks made me think it would be a fuzzy/buzzy distortion box that would only be good boosting an already dirty amp. As it turns out, it's very much a "heavy overdrive" - like a Tubescreamer on steroids! There's plenty of smooth gain, nothing too fizzy and sharp, just a nice warm blues/rock tone. There's a slight mid-hump to it, which adds some punch, but it's not quite as obvious as a Tubescreamer. It is there though.
After trying it through my rig, and loving it, I wondered how it compared to the BB Preamp that's been my long-term favourite overdrive on my pedal board. In fact, it's been my favourite pedal, period. It's been beaten - the Distortion III is the new king!
In comparison to the BB, the Dist III is warmer, smoother and has more Marshall-style grunt. Into the clean channel, and comparing it to my lead channel, it's pretty similar in tone. Perfect for the rhythm tones I need. Into the lead channel, it gives more gain, sustain and a singing quality. Really, really nice. The BB sounds scooped and twangy in comparison.
I later discovered that the Dist III is only £70 new via mail order, so while I didn't get bargain of the century I did OK I guess. If anyone's considering getting a BB Preamp at £169, but thinks they're expensive, grab yourself a Distortion III and laugh all the way to the tone bank :D