I played ...I don't know, hundreds of gigs on one and mostly loved it. Certainly for ease. At times, it sounded perfect, though some specific combinations of rooms and drummers made for bad nights with it.
I sold mine and have had an AI combo and currently have 2 EA setups. One iAmp 500 combo and a micro head with a 10" Wizzy speaker.
Both of the EAs are objectively much better amps sonically than the GK was. Both have a lot more clean, usable headroom. The micro/wizzy setup is nearly 20lbs lighter. I bought both pieces used here at different times. The 500 combo is better across the board and better for anything rock-like, which is less that 1% of what I play, but it's heavier. The 10" as an extension to the combo, scales further still.
The AI combos...I don't love the sound and I found it to be a bit akward to carry around, though it is lighter. I had a piano trio gig for about a year in a good room with a good piano and it was great there, but it didn't always scale to the room and occasion for me. It could be loud enough, there was just a sound that I didn't love. It was probably in there, but I just couldn't always get it out, like I can with the EA amps. Some people feel exactly the opposite. I sold mine to fund the 2nd EA rig.
Nothing wrong with the GKs, you could buy a newer used one for $400 or so if you look and wait and/or get yours repaired. Whether they are as good or better than modern alternatives is a matter of taste, the fact is though that they aren't the lightest choice anymore and haven't been for a while.
If I lost everything in a fire, I would replace the EA Micro Head and Wizzy the next day and maybe pick up an extra Wizzy cabinet when the time was right. Maybe an old AI, GK or EA amp head as a backup when a deal fell in my lap.
I haven't tried the Phil Jones or Genz Benz, I hear they are great as are a few other new choices. Hope that helps a little.
