Those are beautiful boats. My wife and I almost bought a new 3400, but didn't like the dent it would've made in our disposable income, so we ended up going Beneteau.
There has been a lot of chatter lately about Tartan, its parent company, and the quality of their hulls. Some of the threads have been removed after letters from lawyers, but check for Tartan threads over on anything-sailing.com and judge for yourself.
If I'm not mistaken, Practical Sailor did a review of that boat within the past 6 months, so dig around for that.