Well I built it and it works! Actually it sounds quite good. It likes my Strat more than my Duo Jet and has a surprising amount of bassiness to it. So for once I don't feel the need to add any lows.
The hi-cut switch is interesting - it's not just a treble roll-off; it seems to shift the treble or something. Initially I wondered why you would have a treble cut switch if you have a tone control but it does more than just slice off some highs. It's relatively subtle but useful I guess.
Overall it's a bit more compressed than I usually like but it's cool.
Built, definite keeper. I dunno why there isn't more buzz on the pearl b/c after building 2 (this layout and pcb) I can confidently say this little gem is a 9V Klon Killer; I own a storebought Archer & MXR sugar drive for comparison.
Anyway, my advice is socket the leds and try a number of color/size combos as the circuit is very responsive to these changes, I even sometimes found going from 3mm to 5mm to make a noticeable change to tone. FWIW I found my fav combo to be a 5mm green & 5mm IR (purple lense) but a pair of 5mm IR will give you a very mean snarl that also sounds good. I also have to Agree with Hamish in that both switches are very usefull so give them a chance and don't just hardwire it right off the bat.
As I sometimes do with pedals I like, I work out which bits work for me and leave out the bits I don't need. So i built another of these without the switches. I used red LEDs for clipping and simplified the treble so i didn't need the hi-cut.
So now it's just another 3-knob OD - but a very good one! Amazing that there is still room in the world for another 3-knob overdrive. :-) But there really is.
(edit) Just in case anyone is interested - and i have no reason to think that you might! - but here is what I did to the original Golden Pearl in (a) an attempt to simplify it, and (b) make it suit my playing better. I like to prune anything I don't use. Then I can't use it by mistake. :-)
It looks like it's just changing from the 4148s to the yellow diode pairs for clipping. Make sure you have the diodes soldered in anti-parallel (one facing the other direction of the other) if it's not working.