Welcome to the Forum
Unless you are looking for an ugly revolver (or get real lucky), I think the days of the sub $600 N-frames are well behind us.
The Model 27 was the first NEW revolver I ever purchased (way back in the 70s) and I still shoot it today. I have owned two Model 28s simply to have them in the collection. I have never fired either of them and in fact sold off the 4" because of the ridiculous prices they have been bringing
It is not about making money, or which one will be worth more 20-30-40 years down the road when I decide to sell it, I like things that look good, so I would not give consideration to a Model 28 and simply buy a Model 27.
You NEVER hear anyone justifying WHY they bought or shoot a Model 27 over a Model 28, but lots of folks feel the need to explain why they are shooting Model 28s