I'm buying my first guitar and I have this guitar in consideration as I'll play a lot of blues. The thing is, I also want to play quite a lot of some classic rock and blues-rock (Queen, ZZ Top, Guns n' Roses, Lynyrd Skynyrd, AC/DC). So I wanted to ask you experts... How good does that guitar sound when used with the overdrive of, let's say, a Fender Mustang?

Thanks in advance!
honestly if those are the bands you want to play the Epi dot might not be the best choice. it's a good guitar but i think an SG or Les Paul might do you better. the epi is a great guitar for blues and jazz and i suppose if you are playing Izzy's parts for GnR it would work but not so much for slash. your best bet is to plug one in and crank up the distorion to the highest level you would use. if you have no issues you can't live with then go for it otherwise consider some other options.
a dot will be just fine. especially the faded studio one, which has higher output pickups. as long as you don't turn the gain (distortion) on your amp up too high, there shouldn't be any issues whatsoever. plus, they sound great at lower to mid gain levels
Epi Dots are great bang for buck guitars. You can give them a fair bit of drive before you experience any problems as well.

Do what monwobobobo said and push it as far as you'd want to go gain wise and see how it handles it. I've never tried driving one up so I couldn't tell you specifics.