Because the 1187 is a has stamped metal parts and usually w/ rouugh forcing cones etc (so it may pattern like crap), prone to lots of parts breakages (that always seem to happen in the field so bring a backup gun) and it may blow up on you. Berettas are made like older 1100s (machined parts) will fire 100,000s of rounds w/o a failure. Look at the dove/duck operations in S Amer - not many Rems there. You get what you pay for - find a used 391 and they will be $800-1200 (if u need teh 3.5 model) and be happy. Same could be said for Benellis but sometimes inertia guns wont fire low brass loads - need to be broken in more. Btm line if you dont hunt much, dont mind gun failures get an 1187. If you want to pull the trigger and go bang get a B gun.
quote: If you want to pull the trigger and go bang get a B gun
I've been to a skeet shoot where a pair of berettas couldn't get more than 3 shots off without locking up. Guns were spotless at the beginning of the day and after about 2 or 3 boxes of shells they were pretty much single shots.
Any auto is prone to having a bad day in my experience.
I have yet to see a failure of a B gun at any of the clubs I have shot at - you see Rem 110s and now a few versa max's but nvr any 1187s. I shoot a cpl of thousand rounds a yr from 391s nvr a prob and I clean them 2X a yr. One trap/skeet shooter that convinced me to get a 391 has shot 100,000s of thousands of rounds w one failure. Some M1s etc but 1187s are falling out of favor. Both my uncle and I had chronic issues w 1187 supermags - they arent in the gun lockers anymore - he got an SBE11 me a 391.