i prefer the fn-fal but i would like to get a second opinion.
I here ya. IMO... both designs have their +/-.... so to speak. After owning, and testing both (along with an HK-91), we decided as a group to go with the M14/M1A, although the Fal was a very close 2nd.
We started this because we were looking for one rifle type to replace a few others of various calibers in order to streamline our own logistics. ( 7.62x39mm, 5.56x45mm, 30-06, and a few others
1. ERGONOMICS : A personal preference of course.The M1A won out here in our case. If a body prefers the pistol grips, and/or folding stocks.....there is several different types to choose from for an M14, and we also have the traditional style to use as well. IE........ the M1A has more variations to offer in this dept from my hands on anyways.
The best advise I could give to anyone searching for a rifle of their very own is this : Put your own mitts on a few, and see which one feels right for you. How does it balance in your hands? Do you like the location of the safety? How does the action feel? Do you like how the magazine inserts into the weapon ( Direct insertion such as the AR, or "rock and lock" insertion such as the AK for example). Make sure to handle the shorter barreled models as well.
2. RELIABILITY : While both excelled in most of the tests we put them through, the M14 did edge out in favor for one little reason : It's design allows a body to swipe mud/crud off of it's bolt with the hand. The trigger group dissassembles as one unit, so it's fairly quick to pop it out, wipe it down, and pop it back in again, if thats what is needed to get her runnin again. The Fal isnt as simple or as quick to do this, and either is the AK for that matter. FWIW...... the SKS was a close second to the M14, at least in our tests. Very easy to clear the rear sight of mud/crud from an SKS to boot.
We also tested them in a rapid fire sorta thing. ( Dumped 2-20rd mags through them, then loaded a third mag immediately, and fired for groups at 100yds to look for "stringing". The DSA Fal strung vertically from center while the M14S hung in there and delivered it;s consistent 2in group.
FTR.... I'm not a scientist,enginneer, or gun builder by any means. Just a simple "end user" with a few ideas that we tried out. Our testing was done with an example of each, so this by no means covers another example. You asked, so hers what happened...
3. ACCURACY:
Both will get the job done provided the shooter does theirs. We preferred the iron sights of the M14 as a group, which did play a factor in why the M14 had the edge here. All shooting was done in the prone supported position at 100yds and out to 400yds.
We then went to the bench, and started shooting for groups at 100yds with various commercial, and milsurp ammunition. The M14S would reliably shoot anything we loaded up its mag with, while the Fal was choosy about what it liked. (Kinda falls into the reliability format, but ....) I a nutshell... the M14 had more consistent groups than the others.
4. SPARE PARTS:
Much cheaper and easier to find Fal parts then M14 parts nowadays, but at the time we did our tests, they were pretty much even. I haven't priced Fal mags recently, make sure your buyin the real deal when it comes to M14 mags. Current 20rd M14 mags run 25 bucks a pop.( CMI mags at 44mag.com)
5. OPTICS:
Flat top Fals look easy to mount optics to, but I dont have all that much experience with them. I do have alot of hands on when it comes to the M14/M1A, so I'll tell ya what I know from actually doin it.
I stay away from the SpringfieldArmory mounts because sooner or later they all "shoot loose" on me. After hitting the 10k mark with one of my M14s..... my ARMS #18 split rail mount is still where its supposed to be. I'm also playing around with another mount on an M1A Bush rifle at present time, but not ready to make a range report yet.
On a side note....... I have read several threads on the internet about scope mounting issues with SAI M1A's. Apparently some are havin issues because some M1A rifles are not within USGI specs when it comes to the receiver alignment rail on the receiver, and/or the scope mount bolt hole. I have not had this issue, but a company called Sadlak has a simple kit that you can use to find out if your particular reciever is to spec or not.
To date, I have never seen a Norinco, or Polytech reciever that was outa spec, ( 7 rifles), and haven't run across an M1A that's outa spec either. ( 5 rifles. The one Fulton Armory receiver I played with was GTG as well in this area.
ARMS #18 split rail mount set on an M14S Norinco custom build.
OVERALL IMPRESSIONS :
The M14 has more options than the Fal based on my own experience with both. The M14 does better at replacing the motley horde of different rifles we used to own as a group, and fills their specific roles better than the Fal would have. We can all use the same ammo through the same mags, and are all familiar with each others own rifle well enough to keep it in operation if's we had to. ( Havin a tool for every job is great unless your the one who;s humpin the tool box around.

Again...... just my .02
Good luck with your search sir.