which would you get Crosman?

Both are basically the same gun with different barrel. The 1720 is a marauder pistol, but has a .117 LW barrel and only single load. The marauder prod is only in .22 and have 8 round mag. If you want accuracy then of course the 1720 with the LW barrel. The prod barrel is only a crosman barrel. Accuracy is ok but not the best. Ask yourself. Do you want a .177 or a .22 cal. Do you want single load each time or multi shot mag. Do you want accuracy? Both are quiet but nothing compared to the mrod. The shourd is too short to really quiet it down. But you can always add a ldc to mouse fart.
 
A friend of a friend had a 1720 at a match a few months ago that that I was able to shoot. That particular gun shot very well. They also have a nice trigger. The 1720 does quiet well in competition, specifically talking about pistol field target. I've been considering buying one myself. If you want really quiet, the transfer port can be swapped out to give about 6fpe and 70 or 80 shots per fill. But even at 12 or fpe, they're not too loud. 

Just a good solid gun that shoots better than it's price point. I'd do the 1720 before the prod because of the lothar barrel you get in the 1720, as already mentioned. 
 
Ok this is my first PCP. Benjamin Marauder Prod. I’ve had it for about two months. I’m loving it for my back yard plinking and pesting. Now I bought it here off the classifieds. And it has some upgrades. Marmot Militia barrel and a Neil Caluge moderator. It’s super quiet and and accurate with 14.6grn H&N Field Target Trophy pellets. Got these two rats last Monday. Head shots right between the eyes. 

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