Awesome looking pedal DVM and can't leave out great sounding If I didn't already have a modded boss Sd-1 I would be on board for one of these You do have me remodding though already changed tone pot out The boss had a 20k and flattin out between 10 and 1 excellent now with the 2K Now will do my homework and change the two position switch for the three and incorperate the Led Like you said op amp chip changes are kind of minor I have had RC4558P, RC4559P, JRC4558D and Burr Brown OPA2134PA the brown to me makes the pedal more transparent and adds clarity which to me benifits single coil pickup and the splitting of humbucker