The 140 is 1/2" less thick, 1/2" less wide, and 1/4" less long than the 150. I think the horn is cut a little sharper on the 140 as well.
It's definately not a bad price for what it is, but if I were in the market for a Heritage, I'd be on the lookout for a 150 model or better. They're not that much more expensive.