What are the differences in the different modular chest rigs like the Hellcat and MAV?  Also I was going to get a SOE CQB subload to get both pistol and rifle mags on my thigh, but I really wamt modular.  Is there a modular thigh rig I can set up that would fit 2 rifle mag pouches and 2 pistol mag pouches on my thigh?

SOE, Blackhawk and Tactical Tailor all have modular thigh rigs.

Yes but is there a pouch for a modular thigh rig that has pistol and rifle mag holders together like an SOE subload has.  As far as I can tell if you put two mag pouches on the modualr thigh panel there would be no room for pistol pouches.

Also other than the Hellcat having mags behind the webbing and the MAV having a velco map/utility pocket instead are there any differences in the two in method of attachment, quality, etc.

They're both great quality. The advantage that the Hellcat gives you is that you can carry 6 mags without giving up any PALS real estate. You start out 6 up. The MAV and the Hellcat both offer one piece and two piece fronts. For their two piece, TT offers a nice shoulder yoke.

Lightfighter sells the MOLLE attachable SOE Patrol pouches as well.

Anything else? You want a beer while I'm up?

Will the TT yoke work on the Hellcat?  Or are they set up differently?  Can I get a Coors Light?

As far as I know, the TT yoke will not mate up to the Hellcat as is, but SoTech is happy to do custom work.

Is it beer thirty already?