There is no replacement for displacement. For $60 difference I would be all over the 372. That is my honest answer to your exact question.
There are, however, instances where a 60cc saw may be better suited to the application than a 70cc saw. Those instances are few, in my opinion.
If a healthy male that USES a saw could only have ONE saw, a 70cc would be the size to have, without a doubt, IN MY AREA, In My Opinion.
I would rather have a GOOD, USED 50cc/70cc combo, than ONE NEW 60cc. I own, and use, a 262xp and a 359. What they do, my 372 does better.
A GOOD 50cc saw is a very wise choice for many people's honest needs.
The ACTUAL difference in weight between the 'classic' 372 and the 372'XT' is something like 3-6 oz. I have a hard time getting over that small weight gain, but it really is negligible on a 14 lb saw.