My friend's Accord was completely brutal. The car leaked, and the back seat would get soaked with water, after five years of complaints and never fixing the issue, they sold the car... Honda would not buy it back and they waited far too long for the lemon laws (or so they told me, I'd have been more forceful). Drivetrain problems, wheel bearing problems, something to do with the steering, it just never ended. Anecdotal? For sure. But I rode in the back of the car to a wedding with them when I discovered that the rear seat was soaked through and got to hear the whole story about how it kept re-occuring and nobody could find the issue.
I'm not familiar with the 2009 A4. My only exposure to the B7 was my friend's S4 with the old V8. I do know, however, that the Audis did have an issue with ring sealing and oil consumption for those people who did not drive them "hard" enough when they were new. Audi dealerships recommend you go out and beat on the car mercilessly when they're new now. When the salesman handed me the keys to my S4, he told me to go out and see what it can do and to drive it like it owes me money.
Take a look at APR's available modifications for the A4:
http://www.goapr.com/
Pretty modest for the 2.0L without switching turbos, but it's 170awhp. If you look up the S4, they're pushing 400awhp with $1800 in mods! That's where I'm headed once I put some more km on my car. The best part is, it looks like a rental car... practically invisible to The Plod.
If I was buying a low-options car today and leasing or taking a loan, I'd probably get a Q50. $45K buys you a hell of a nice car. Or find a used G37. Make sure you budget wheels + snow tires for it, just like most sport/sporty cars on the market, because the stock tires are completely inappropriate to snow or ice.
Oh yeah, for those who haven't seen it, Audi A4/S4 interior. The next gen will get the A7 MMI which you can use gestures/writing on as well.
Before someone asks why I didn't get a high-option Q50: the Audi has a supercharged 3.0L, MMI, sport diff, Bang & Olufsen, DSG transmission, easy mod potential and I hate that the touchscreen in the Q50 can't keep up with your gestures... that aggravated me to no end. The Q50 was quite a bit cheaper, mind.