I am in the same boat.
I purchased a 3 year Kaspersky Internet Security lisence and was happy with it until KIS 2010. Running it on a Windows 7 PC with SSD, it took it to it's knees although I actually returned the SSD to Intel who agreed with my claims that the drive was faulty.
I have also noticed a degredation in performance under Vista 64.
My Kaspersky liscence expires in about 50 days so I am looking to move onto the newest, latest and greatest AV with Firewall and the like.
ESET was my likely choice as when I purchased Kaspersky Internet Security, those two were the best on the market.
Any opinions on which one is better than the other .. or is it a safe bet that if I go with either of them that I'll have very few issues?