thanks for the replies. I pretty much stay away from the 34-12. I'm not worried about the chainline hurting anything but I hate the noise. It has got to be causing wear on the pins as well.
It is a ratio that I like and the extra shifting to get to a similar gear on the 50 is often a nuisance.
Comapct cranks have their uses but I sometimes think I would be better going back to a 53-39 and just getting a cassette with a few cogs with higher teeth counts.