For those of you who have played using the Ampeg Portaflex series cabs and heads, I have a couple of questions about them. If everything goes right, it seems to be the go-to amp for my needs, assuming I buy the PF500 stack that Ampeg sells. 1. How loud does it get without being muddy/distorted? Alot of the amps I've played before get gunked up sound quality at suprisingly low volumes, particuarly on the B string. 2. Overall sound quality? My local GC doesn't have one, so I am wondering exactly how great it sounds in person. I've seen some videos, and listened to testimonies, and it seems spot-on. 3. Adding extra cabs? I see from the specs that the amp is 4 ohms and the cab is 8 ohms. Perhaps I should consider getting an extra cab of similar quality and size? I like playing loud, and this seems wonderful on a medium-small budget. If I get another 1x15 or 2x10 cab to go with this, how much would I be benefiting. 4. The 2x10 or 1x15? Ampeg offers the 2x10 or 1x15 cab for the PF500 stack. Which one should I get? I know there are countless threads for this, but really what is the difference between the two?