I used a late 90's 1215 300w combo for a couple of years and it was a pretty good sounding amp (very loud), although it was a bit flaky in the power amp stage when I first got it. I changed it for one of the newer 1215 500w amps thinking the extra headroom would be useful, but apart from the extra weight it wasn't as good. I used it most of the time with a 1518c cab which was light as a feather and sounded good and it did the job but is wasn't anything special. The GK kit I use now is much lighter and sounds better and potentially goes a lot louder if required.
It's a shame, when I played in pubs and clubs 20 - 25 years ago I used a 150w Carlsbro head and 2x15 cab that felt like a wardrobe when I moved it round (in my Mini), at that time Trace was the new kid on the block and for me was lighter and better sounding - but so expensive then. Now, it still sounds much the same and weighs the same - I guess as others have said we have all moved on apart from them. The current cabs are good and I would still use them, but the electronics aren't as special as they used to be.