Re: RIP Jim Marshall
Jim Marshall is a legend, and he very well deserved it. And still Jim has been extremely earthed all his life.
As for amps - now that this aspect has been mentioned - and ignoring the historic impact of Marshall as a brand - there are literally _hundreds_ of great amp manufacturers out there. So there is no "best" in this category of course. Who of us has the "best" taste to judge??
Personally I've always avoided anything Marshall, Fender & Gibson in my own gear arsenal (guitarist obviously). Why? Not because this stuff is bad (quite the opposite usually) but because... everybody uses them. So do I have to use it as well? As if those brands were the only ones to choose between... (Admittedly I have something Marshall... Their Guv'nor pedal booster is top notch. As for amps I have a Mesa. For now - this could change.)
Marshall amps sounding raw does have one sonic advantage though: Due to this property, usually they cut well in a band context or mix. Still I prefer it a bit more creamy.