Dear Wolf: Thanks for the update!. Unfortunately, I've already had to replace my 200MB's speaker. Twice in fact, because the first time I replaced it by an accordion-type cone edge one, and also disliked the result. I ended talking to a music student of mine, who also happens to be a wonderful speaker repair guy. So he completely rebuilt the OEM speaker (which, as I've found out on the internet, happens to be a Pyle Pro, same case on GK's ML250 guitar amp -same series, even same year!-, which I also own and love) taking extra care of using the best materials around, and it ended sounding fine. Then I had some trouble with a faulty external speaker cable (I like to use it, for mid-smaller venues, in 4ohm with a custom external, Eden loaded 1x10 front slot- vented cab), and blew up something in the circuit. Again, found the schematics and took it to a repair guy who gave it to me working as a breeze... except for the caulk sealing, which was all gone, so it rattled all the way. AGAIN... had to disassemble it, and reseal every corner -I used silicone for this-, and voil?!. A nice tip: The 200MB has a rubber stop that screws unto the back panel and presses against the speaker's magnet. Mine shrunk a little, and changed the sound a little bit, so applying silicone to both ends of the rubber stop helped a lot.
It's a bliss to know the 150 has the speaker front-mounted!. I'll make sure to get ahold of one whenever I can, since the time I spent with my 200MB in repair shop, I really missed it a lot (have other rigs to work with, but are either too heavy, too big, or too complicated for what I like to do with the 200MB).
However.. . I laid my eyes and my ears on one of those newer SWR Headlite amps, and yummmmm...! Maybe one of those, with the lightest of my 2x10 cabs -certainly NOT my MesaBoogie RoadReady, which sounds delightful but weighs A TON!- or the Eden-loaded 1x10 would make one of my small venue jazz gigs a dream...

Just have to set some dough apart

. Anyone using one of those?
JC