What can I expect to hear from a decent analog FM Tuner?


Will these provide something warmer, different or enhanced from Streaming or CD?  I currently have a vintage Kenwood 700 M amp that I am using with Benchmark DAC2.
puffbojie
I have a McIntosh tuner in each of my 2 systems and listen to FM radio a lot and mostly because I am lazy. It works for me. 
FWIW, I have a couple of excellent vintage tuners and a local college. This AM I was listening to some classical music on my inexpensive Yamaha T-85. The audio was as good, or at least nearly as good, and either of my CDP's. Your main limitation on  FM radio is the quality of your station(s) and your preference for their program.  
I mostly listen to WWOZ (New Orleans community radio) over the airwaves. Many of the programmers play vinyl from the their own collections as well as cd's and the stations extensive digital files, and on occasion the station broadcasts live in studio performances. The signal is not overly compressed (unlike commercial radio) and can sound as involving to me as my other sources.

I really like the idea of broadcast radio, but as others have said it will only work for you if there are stations you want to listen to. In most urban areas there are public stations (i.e. NPR--mostly talk now,) community stations (often volunteer run and more enthusiastic than professional--which is all to the good in estimation,) and college stations (unfortunately too many have become NPR stations--I look for ones that are still student programmed.) Out in the sticks or in newer communities there are far fewer of these public resources and you are at the mercy of commercial radio which is generally not worth the effort. It is the programming that should drives the bus here--not searching for the ultimate audiophile experience.

Depending on distance and topography, you may well need a good antenna and a highly discriminating tuner to get a good signal--especially in stereo. In more favorable environments a simple dipole antenna can work fine. I favor vintage analog tuners and mostly use a McIntosh MR-78 although I also have a Pioneer TX-9500II that may sound better (and is a much better value--but not nearly as pretty,) and a Marantz 20B. Lesser vintage tuners are pretty easy to find and many still sound good so the cost of entry shouldn't be too high.
A good tuner even with just a ribbon antenna will pick up station great .Depending were you live .I'm on Long Island N.Y.