Have you fired both types in thier relative "stock" format to find which type you prefer?
I have owned both examples in the past ( DSA FAL, SAI M1A, NorincoM14S,, along with an HK91.... and had them for several years comparing them, and getting familiar enough with both to make a decision on which one me and mine preferred and why.
This is what we came up with, and most of it is based on personal experience/preference.
RELIABILITY : All were very reliable, and no hassles with them here. Being U.S. Army Infantry myself, I have more first hand experience with the M14 service rifle vs the FAL, and have confidence that this type of rifle can handle any types of extremes in relation to climate, terrain, etc..... ( I have used it in several different extremes across the globe, ranging from Iraq, Afghanistan, Panama, and Africa... so my confidence with this type of rifle is fairly high because of this.)
FWIW, our M1A/M14's did seem to reliably feed a wider range of ammunition better than the FAL.... even though the FAL had an adjustable gas system.
ERGONOMICS/ MANUAL OF ARMS/OVERALL BALANCE : The M1A/M14 was the definite winner in this category for me and mine.... and by a long shot. The location of the safety in relation to the op-rod handle was a big reason for this, along with mag changes. The design of the M14 lends itself very well as a "point and shoot" type of rifle, and it felt better balanced as compared to the FAL.
Unlike others, I dont believe that a pistol grip is a mandatory item for rifles such as these, but with the M14/M1A...... one has the option of using either or.
The M1A/M14 works well for shooting right or left handed from my experience, and is something I do consider to be important when it comes to a rifle.
LONGEVITY/DURABILITY : Either would make the cut here from my experience. ( Provided that both are maintained properly)
CURRENT/FUTURE PARTS (magazines) AVAILABILITY : Several companies are now making quality parts for the M14/M1A as of now, and to include magazines, but I don't see alot of Fal components, other than milsurp kits/mags that are quickly drying up stateside. If something were to happen to DSA, they might become so scarce that it wouldn't be worth the trouble.
We have no issues with the current production checkmate Industry mags, or 60's era GI mags. This includes M14 government rifles as well as the semi auto clones. CMI 20rd GI magazine NSN = 1005-00-628-9048.
NOTE: This same 20rd magazine is also the same magazine that Springfield Armory Inc (SAI) sells at 55 bucks a pop. The only difference is the logo stamped on the side. Calling USGI crap, then calling SAI mags wonderful equates to lack of knowledge regarding this...since they are both one and the same.
I cant comment on the Korean mags, as I don't have any. Norinco/Polytech mags that I have had since the early 90's still work fine.
IRON SIGHTS : We preferred the M1A/M14 here. They can be dialed more precisely fo a given load, are less prone to damage, and has a wide range of options to choose from depending on the application. ( Examples include different sized rear sight apertures and different sized front sight post widths.)
FWIW...... There is quite a big difference in the irons sights of a Socom vs a Super match for example. This, combined with the difference in sight radius will show a big difference when actually looking down them prior to firing.
OPTICS MOUNTS/STOCKS : Both have plenty of ways to mount optics nowadays it seems. It all comes down to where a body wants them, and the costs involved. I'm currently running 2 different receiver mounts for the M14/M1A.
The ARMS #18 split rail, and 2 different versions of the Bassett mount. Both types have their pluses and minuses, but I prefer them over the SEI/Sadlak mounts.
As with most things made out of rails, the more one adds to the rails, the more weight one ends up with in the end. I don't care for alot of rail space, as I simply do not need it for adding things to, nor due I need the additional weight that comes with it.....but others mileage seem to vary a great deal when it comes to adding things to rails.
As I mentioned before, I am rather picky at what should or should not be added to a rifle because I like the way it feels and handles as is (overall balance), but also like to use optics. This really comes down to personal preference to such an extent, that one really needs to try it out for themselves at this point. (Just my .02 here)
OVERALL COSTS : Nowadays, the FAL costs less, and is the clear winner here.If this is the end-all factor in a decision on which to purchase, then it should make decision easier I would think. In our case..... we went with what worked the best for us
END STATE :
I sold off the Fal's and HK91, along with several other rifles of various design...... and haven't regretted it since.
I like the 18 "ish" inch variety personally.........
The one at top is an M1A-A1 Bush rifle built from the factory with an SAI (Wilson) std weight 1/11in twist non chrome lined bbl, and all USGI parts.
The rear sight aperture is std GI, while front sight is 0.062 in (NM)
(I use a Bassett mount with this rifle when I want glass) Sight radius = 22.75in
Weight (as pictured) = 8.5lbs
The other is a custom build using a Norinco M14S receiver, and Criterion (Kreiger) 18.5in chrome lined std contour 1/12in twist bbl. Parts makeup is a mix of GI/SEI/OEM ...along with ARMS #18 split rail receiver mount. Rear sight aperture = std GI, and GLFS-H = 0.062in.
Sight radius = 21.25 in. Weight = 8.9lbs.
This one was built by LRB ARMS using their M14SA receiver.
All NIB/like new USGI parts with same bbl as the M14S mentioned above. SEI GLFS- DT 18. Std GI rear sight aperture. Front sight post = 0.062in
Weight will be about the same as the M1A-A1, and sight radius will = same as the M14S..... or very close.
Im thinking about installing an Ultimak M8 rail/red dot sight on the M14SA, but haven't quite made up my mind yet. This combination should allow for co-witness with the iron sights, but wont know for sure until I get my hands on it all. I also will use a Bassett mount for a more traditional scope, as well as a 3gen Raptor NVS.
http://www.bassettmachine.com/prod_smpr.htm
My next one will be built off an LRB Arms M25 receiver..... which might be of interest to you regarding optics mounting.
http://www.lrbarms.com/m14receivers.html
11B