Congrats!
Enjoy your new Vulcan! 
If the 'Mech brings you fun, run it.
Some people like "Bandit", because it has its ballistic hardpoints in side torsos instead of in those low slung arms that Mad Dog C offers.
Indeed. I see
Revenant somewhat more frequently however.

For my part, I just positioned myself in such a way that the low mounts weren't a terribly significant issue.
Although now that you mention it, if I ever get my hands on a
Bandit, I may attempt a quad-Gauss build using the C's arm pods... On the other hand, it's probably impractical on a
Mad Dog due to the inability to add further weight-saving tech to an OmniMech, and thus probably not worth the trouble. I'll likely save that idea for a
Kodiak or something.
I was surprised anyone actually still ran quad-Gauss builds, though. I would have thought their mechanics would have killed that idea dead a long time ago.

Apparently not!