If it's of any use, I used a Superbe Pro Track adjustable BB with sealed bearings for a while. Sounds like the bee's knees, right? Nope... while it was indeed nice to have adjustable chainline (and I never had problems with loosening, but I wasn't brakeless then either) the bearings flat-out sucked. I killed one in less than a year. My LBS loaned me another one (they have an amazing collection of stuff) while they looked into replacement bearings, and I froze that one in less than a month. Turns out the bearings are an odd size, and would've been $50/pair to replace. Cheapo Campy bottom bracket works way better now anyway.

Way OT, and I don't have any advice on english threaded BB's. Sorry.