i had sirius for a few years but when they merged most of the channels last year i cancelled. i only listened to a handful of the stations and most of them were replaced with the xm version that i didn't care for. stern is good, but he ain't worth $13 a month. another thing that pissed me off was the fact that you have to pay extra now for the specialty stations that one side offers. for example, if you have sirius and want to listen to nba games, nhl games, mlb games, etc that were all part of xm you have to pay an extra $4 per month. if it's one big company now why can't they just give you all the channels?
as far as sq, i had a portable unit using the sirius hardwired fm modulator. the sq was lightyears better than the built-in wireless transmitter but less than normal fm radio. all the newer portable models have crappy fm transmitters. a few years back the fcc said that the older ones were too powerful and made them dumb-down the quality.