Im looking to purchase a nice combo amp at guitar center/ musiciansfriend... and was just wondering how big of a difference it is if i just get a single speker versus a 2 x 12. Also, is there a huge difference between 30 amps of power and 50-60? I do not gig, i just play my guitar for fun.... mostly classic rock to grunge. Thanks!

and if you have any suggestions about combos' let me know!