When I ordered my Mark III, every musician (not just beginners) I knew, told me that it was a stupid move. Everybody said that Boogies have great sound but they always have major problems with power supply soon after you start to use it. My 1988 Mark III has been reliable of course.
My Boss CE-2 Analog Chorus pedal is even older. When my band mate bought Digital Roland synthesizer, it had the chorus effect of course. He told me that Boss effects are actually Roland effects and that the syntesizer's chorus sounds quite the same as my pedal. So I connected that pedal between the synthesizer and a mixer and told him to try. He agreed that the CE-2 sounded much better.
A keyboard player I know said in 1983 that great guitarists don't use guitar effects. Well he didn't know much about Hendrix, Clapton, Page, Gilmour, Kaukonen and Beck. That comment came after I told him that I'm going to test my friend's flanger pedal.
When I was jamming with musicians I knew, one multi-instrumentlist said "Hey, that's a good old Mesa". I told him that it's a almost brand new, about six months old. And he replied "Does the company still exist". It was 1989.
I have this smart cousin. She's smarter than me but she doesn't know much about music or instruments. She hasn't even tried to play some instrument. When I told her that I will spend lots of money to buy an amp that's good enough for highly paid professionals, she replid something like this: "The development in digital technologies will soon make that thing useless".