Absolutely. They are tanks. I've used my 64 B-15N on a regular basis on gigs for the past 12 years and it performs like a champ. The 77 B-15N I used to have was the same way. Had a new power transformer installed on the 64 3 years ago, but the old one worked fine...it was just bashed in and looked ugly. The only thing I've done to it in the last 3 years is replace a preamp tube and the original filter cap finally went bad a couple years ago. They might need a tube now and then, but the likelihood of being stuck on a gig is extremely low with vintage B-15's as long as you take reasonable care of them. Don't have to baby them...just try not to drop them too hard from too high a distance. You could break a tube