M-203 is a most enjoyable tool to have in the tool kit, and the chalk rounds are a hoot and really good for training!
If money were no hindrance, I vote 40 Mike Mike Bofors Powered Mount AA/multi use gun! Scratches the Destructive Device AND Machine Gun itch
Or, even better Mk-19 Chassis mounted Bofors Twin mount, kills several birds with one set of papers!
I most enjoyed the M-79 while I was in RVN and kept two of them, one on each end of the bar, in the Company Club. They had been cut down including the Stocks so they had a Pistol Grip and the Barrels were shortened to stop at the Forend. Very Handy indeed!!!
Oh, the one advantage the -79 has over the M-203 is that the M-79 was able to fire a longer Flare Round. FWIW I assembled the very first XM-203 in Vietnam. What we found was that if a Colt Rifle was used, the assembly time was 45 minutes, while if any other Brand was used it took close to twice that long.
Actually in the process of adding more models to get a stream out beyond 30' of the reasonably priced units. The max spray is well over 100' and are priced like a Nighthawk pistol. We will have some fun next quarter.