For my 2 cents worth bought similar rail style single coil sized PUP's a couple of years ago that had 4 wires, etc. Used mini DPDT on-on-on switches and could not find any discernible sound difference between split/series/parallel and ended up extracting them and installing Entwistle Darkstars which for the price sound awesome. Acknowledge they are more LP sized PUP's but it proves that there may just be better options out there without reverting to Seymour Duncans or Di Marzios.
