You can test your luck on the Godfather's Wheel of Weapons mission on Coney Island!
For the price of 2 Favor Points per spin, you can try your luck on the wheel. You could win a very rare and expensive Limited Edition item! But with all gambling, you also have the high chance of not getting so lucky. So step right up! Give it a spin!
Just to note, from several experiences, it is possible to win an item that makes the gamble worth it. However, the items on the wheel change each spin. For example, the Experimental Laser Rifle may be available during the current spin but on the next it won't. Sometimes the wheel consists of several LE items and most of the time it consists of several low-cost items. The best advice is to use your Favor Points wisely. If you have a fair amount and don't mind risking your points, then give it a shot a couple of times. I have used about 200 FP on the wheel and won the following: (3) Natasha, (3) Window-Pane Overcoat, (4) Dragonskin Vests , (1) Trained Hit-Man, (7) Set of Glock 17s, and (5) Minigun. So look at it this way. Those 23 LE items cost me only 200 FP. Do you math and you average a LE item about 23% of the time. Heck of a bargain.