Probably nine out of ten people on this forum is going to tell you to get a used one due to perceived quality problems with S&W. I have had two post-lock smiths (686+ and 617), and, while I ended up selling them, both were fine weapons, every bit as good mechanically as my older smiths. That being said, the cost of a new 27s are nearly as much as the old 27s (in good shape), yet the resale value on the old 27s is generally better.
Another cost concious option is getting an older model 28. The differences between a 27 and a 28 are (mostly?) cosmetic. I had a 27 but sold it for a slight profit when I realized I just enjoyed the 28 at least as much. A model 28 should cost quite a bit less than a model 27 in similar condition.
BTW, my next smith is going to be a 627 pro. Eight rounds of 357? Heck yeah!