I wouldn't get too caught up in specs. The human ear would never be able to perceive a difference in s/n ratio unless it was very large.
Also, I'm kinda leery of FM sensitivity ratings. I've actually swapped in decks with better ratings and have gotten worse reception. I think it's only useful when comparing decks of the same brand, as they've likely gone through the same testing to determine their rating. I've got a Blau in my RX-7 that's rated at something like 18dBf and does much better than the Clarion in my truck rated at 11dBf.
You can always go satellite.
I think you'd get some benefit using an 8ga wiring kit when installing one of these new higher power decks. There's been a lot of posts about head unit illum dimming lately. Could either be a weak ground or too small of power wire.
