I have FM2n, FE2, and the 24/2.8 AIs, 50/1.4 AIs, and 105/2.4 AI. All great great gear! The AE on the FE2 is good, but I prefer to shoot all manually. If you use the meter (I generally don't), the needle meter on the FE2 is a terrible pain in the ass if it is not brightly lit (its invisible). The LED meter on the FM2n is better, although doesn't provide the same level of feedback as the needle. The nice thing about the FM2n is that you can shoot without a battery. With the FE2 you are limited to 250 without a battery.
I didn't pay that much for my get up. I think ~$100 USD for each camera. The 24mm was $200, the 50 $120 and the 105 about $120.