You're opening up a whole can of worms here. Firstly, watts are really pretty irrelevant when the efficiency of the cabinet and drivers are equally, if not more important. Broadly speaking, cheap, badly made stuff will advertise as very high wattage but doesn't convert into a good, or loud sound. Quality gear will achieve way more with much less advertised power. A decent 300 watt amp will melt your face but a cheap 1000 watt one will invariably sound crap at any volume.
You then have class d versus analogue or valve amps but we're now disappearing down the rabbit hole.