First you gotta ask yourself, what is a better tone to you. Heard your favorite guitar player and really loved his sound? Is that the tone YOU want to be able to get with your fingers and soul?
I think the guys here have told you, wattage don't equate to 'tone'. So relax and know that bigger/ isn't always better.
You can tell if it's tube or not by looking under the hood, or at the back of the amp. See them glass bottles/light bulb kinda things that glows when the amp is switched on, thats your tubes. If it does not seem to have any, like most amps you would find at jamming studios, thats it, it's a solid state.