I had an extended slide release on a full house 5" Gov't Model that was built by master pistolsmith Jim Hoag in Canoga Park, CA. I wasn't a fan of the device at all. I guess it depends on the size of your hands an how you hold a 1911, but I prefer the stock short thumb safety and slide release over anything else on the market.
Here's one of my Hoag guns w/extended King's slide release. I have medium sized hands and would still disengage the extended slide release on an empty mag every time.
