I have the 390 from Wal-Mart. I won it as a door prize at a tournament. Great little gun. Recoil is very very mild, but I normally shoot an O/U...
This might start a war, but here goes...
I like the 390 much better than the 391.
When you remove the barrel of a 390, you also disassemble the gas relief system (much easier to clean). No annoying little spanner wrenches. Also, the plug is easily removable on the 390.
391's have a rod in the magazine end cap that is a pain to remove, and if you do, you'll destroy a little star washer that you'll have to hunt down and purchase before you reinstall it. (Horrible design on that)
Whichever Beretta autoloader you get, make sure you use anti-seize on the fore-end cap. Oil won't work very well, and grease ain't much better. The end cap is very prone to seize to the threads on the endcap (probably due to steel/aluminum galvanic reaction). If this happens, there'll be some replacement parts needed (about $50 worth).
I clean about 7 or 8 guns on a monthly basis for some of the folks at my club. There are 390's, 391's, and Browning Golds in my little group. Most have ~500-1000 rounds between cleanings. I'm not a gunsmith, but I'm a tinkerer and an engineer. I see all three guns regularly and under high usage conditions.
Here are my opinions on the guns in a nutshell...
390, 391, and Gold have VERY tame recoil and shoot well. All are equal to me on this point.
Gas pistons are a real pain to disassemble and clean on a Gold. (If you decide to disasssemble one, a Eisenhower silver dollar makes a good tool, but exercise caution. The internal spring is STIFF, and you must have patience and good hand/wrist strength to reassemble.) Gas piston cleaner won't clean the piston even in an ultrasonic machine in 3 hours. Neither will Shooter's Choice, ammonia, nor kerosene. Let it soak in gas piston cleaner for a few hours, then disassemble and clean with shooters choice and a bronze brush. ADVANTAGE Beretta 390.
Gas relief valve is tough to disassemble and clean on a 391. Wrenches are finnicky to use. Beretta took something good from the 390 and made it complicated for the 391.
Plug is a pure pain to deal with on a 391. The 390 and Gold are much simpler to deal with.
Beretta's are more annoying to remove and clean the bolt return spring. The cap on its tube is also the stud that attaches the stock. Use two nuts jammed together to remove and replace. The threads must be clean and dry and coated with Loctite 242 (the kind that is NOT permanent) before reassembly. The Browning has a plastic spring retainer that pops right out once you remove a pin.
Maybe this is more detail than you wanted, but you can't go wrong with either for the way they shoot. The 390 is easier to maintain than the 391.
Whatever you get, KEEP IT CLEAN!
Good luck and break a hundred!