Best thing to do ,is come and try it. Probably better coupled with a 15, but not absolutely sure. I don't belt my gear, to find out how loud it will go, so no expert. Easy for me to set it up for trial, but remember, it's 4 ohms. I do have amps that run at 2 ohms, and I also have a Trace elliot 2 x 250 (real ) watts RA500 power amp, that I used to use when I was bi-amping, usually out-of doors , so, plenty of options to try. BTW, I'm really into retro bass gear, it's a sickness of mine !
My guess is that Ampeg built this as a smaller version of the 8 x 10 , to be used in more normal sized venues, rather than Stadiums. Just a guess !