As far as epiphones, I just sold a studio that I couldn't get along with. It had a big baseball bat neck. The one I have now much thinner. Also the studio had a raw feel, the standard is poly. Can't speak for Gibsons as I've only played a handful.
I've got a Dot, and the neck is a bit thicker than my mate's mid 60's 335, but I've played them back to back, and after a few minutes with either I'm not conscious of the difference. The fretboards feel very similar (ie, flat).
Interesting feedback - virtually all of the Epiphones (335 or other) that I've played over the last 10 years have had slim-D profile necks?! They're reasonably wide at the nut (1-11/16" I guess), but definitely not chunky.
The only exceptions I can recall are a '58 flying vee I owned, and a firebird studio I played once?