I used to use one of these (stock) with a JCM 800 for gigs and recording back in the early 90's. Great, focused, chunky tone. You can pick one of these up for cheap, and they are convenient, light, easy to transport, etc.
It dawned on me one day to try out some old alnico Jensens in place of the newer ceramic Celestions. So, I tried installing two (because that's all I had at the time) and Whamo! I was hooked. I eventually found two more p10n's and wired in 4 of them bad boys. My thought was that I might get close to the Tweed Fender Bassman (holy grail) sound if I could just get a proper tweed circuit hooked up to this. I've tried a '57 Champ and a '51 Pro to great effect. The Blackface Bandmaster is a perfect match, and with a Tele in front, look out!