I been playing metal for a long time now. Love it, both amps i mentioned can do the job,all you would need is a high end distortion pedal. Especially with the Marshall.
And check out blackstar HT5 metal tube amp. This one kicks a$$. It would cost ya $499 ,and if you go to musicians Friend ,they would knock off 10/15% off.
Unless you have that kinda off dough for a mesa. I would go with blackstar ht5 metal tube amp. It even has a metal front cover. Google it. As far as why mesa is so high dollor. I really don't know. I know i would love to have one. But untill i start making big money with my music,it can sit at Sweetwatar. If i had to geuss why there so much money. I would start with,were are they made,the parts they use,there design, quality work man ship.
Its almost like asking why is a mercedes so expensive, in a way. Good luck. Do you have a band or are you goin solo. Pls don't take this the wrong way, but i think you said you have only been playing for 11 months now.
I honestly think that bs metal amp is up your alley. Don't let 5 watts fool ya. My 5 watt is so loud,im thinking of buying a one watt so i can push those power tubes.
That's when they sound best,when you push those power tubes up on high. ..goodluck.