I ordered a Bad Bob Booster recently, made by RGW Electronics, http://www.rgwelectronics.com/ , from Analog Man, http://www.analogman.com .
I am very impressed, it does exactly what they describe it to do. It drives your tube amp harder, giving you a better sounding, stronger overdriven tone. I loved my tone that I got out of my Peavey Classic 30 before the bad bob, but man, with the bad bob, its a fuller smoother hotter sound.
I'm not gonna get into too much detail because everything there is to say about it has been said over at harmony central, http://www.harmony-central.com/Effects/Data/RGW_Electronics/Bad_Bob_Boost-01.html
It really is as good as it sounds. The currently first review is just some guy bashing another dude's review, you can just skip it.
As for construction, it is very well built, quality parts because these aren't mass produced, they are hand wired. I looked inside, everything is very neat and clean, I'd be very surprised if I ever had any trouble with it.
Overall definetly worth the money. I know that $129 for a pedal with one knob might seem way overpriced, but believe me, they are well worth it. For overdrive I always leave it on, its literally a better tone knob. For clean I don't always have it on, sometimes you don't want a slighty overdriven sound.
I'll be hanging onto this pedal for a long time to come. I really suggest some of your with tube amps check it out.
The first time I heard a Beatles song was "Let It Be." Some little kid was singing along with it: "Let it pee, let it pee" and pretending he was taking a leak. Hey, that's what happened, OK?-some guy