I honestly don't understand why this pedal doesn't cost more than it does, as its relative quality far outweighs its price.
I opted for the LPB-1 over an MXR Micro Amp purely based on price, and safe in the knowledge that Electro Harmonix equipment is consistently high quality. Having played through both pedals, I cannot see any difference in sound or quality, only that the EHX is significantly cheaper.
At lower volumes, in front of the amp, the boost is relatively clean, but breaks up my Orange head beautifully when pumped up. In the FX loop the boost is totally clean.
The casing is sturdy metal, the switching is silent and even the plastic knob seems very robust.
I have noticed that there is a bit of a 'pop' when the pedal is switched on or off, which is the only downside. This could be remedied by installing a higher quality switch quite cheaply though.
An absolute must if you need a boost pedal on a budget.