Can't comment on the BLI "Daylight", but I do have a full set of the MTH cars plus one articulated coach. I like them a lot. Very nice detail, beautiful--and as far as I can tell--extremely accurate paint. Very smooth running cars.
I changed the couplers to Kadee 'whiskers' on my cars, since I don't really trust the plastic couplers that came with them--a train that long is heavy, and I didn't want to have to worry about the couplers failing during running.
Which leads me to the only quibble that I have with the cars--as set up, they're designed to work on 22" radius, so there's naturally a space between the full-width diaphragms. However, adjusting the coupler boxes for close coupling results in a train that is limited to a 48" radius. Since I have 36" radii on my layout, I'm going to have to come up with some kind of solution for close-coupling--possibly converting the cars to long-shank Kadee coupler boxes. I"m just not comfortable with the space between the cars, especially since all of my Walthers passenger cars run with the diagphragms touching.
But that's my only quibble with the cars. I think they make up a beautiful train. All cars are lit--which seems a little 'overkill' for me, since the Daylights did not run at night. I haven't attempted to get into the cars to 'populate' them as yet, the instructions for opening them up seem a little complex to me.
Here's a partial shot of the train on my layout--the locomotives are a re-worked brass Balboa GS-4 and an Athearn Genesis MT-4 running as road locomotive and helper, respectively.
As I said, I like the cars a lot. I think that MTH came up with a real winner, here.