I am looking for a 1.75" belt, maybe a two piece belt? I shoot a 2-gun carbine/pistol competition. How is the DSG one? Would I be better served by a regular 1.75" belt?

I bought one several months ago and have been using it for USPSA.  It works great, at least when compared to a normal leather belt and paddle holster.  

Pros - the buckle is very secure
Stiffer than a normal belt (though not as rigid as i expected)
Good price....$69 at DSG right now.
Use a little velcro to keep your mag pouches and holster put on the outter, and they'll be the the exact same spot every time you put it on.  

The only real con i can think of is the the buckle can prevent a mag holder in that area, doesn't matter if you aren't allowed to store mags or holsters there though.  

I like mine.  

FYI:  I have a 35" waist and bought a large and it is almost too big.

Or just buckle it in the back.

I run one for USPSA as well. Works great.

Could you wear the inner belt as a regular belt for day to day wear?  
Is the outer belt thick enough to hold Mag pouches and holsters in place by itself when donning and doffing or does it have slop that is secured by the under belt?
Thanks

The inner is  a stiffened nylon belt with velcro. It would work for day to day.

Pouches all depends on how they are built. Mine stay in place with no issues, velcro is just holding the outer belt up.

I have one & have been using it for 3 gun & idpa. Going to get another soon so I don't have to unthread for holsters as much. When I do I'll stick some Velcro on my current setup to keep it in place.

Added benefit is that the loop is on the inner belt as opposed to most of the others, if the inner was hook it would probably start tearing up underarmour or other lightweight synthetic shirts.