I've had an SR762 since last NOV, and have had a few 18 and 16 in bbl M14 types for years now.
My M1A Socom started out in life as a SOCOM II, but I didnt care for rails, as it added weight tore the overall balance apart. Ended up selling off the rail system, which left me with a synthetic stock minus the front sling swivel. ( It was back when SAI was still utilizing M14 synthetic stocks.)
My M1A-A1 Bush rifle weighs out at 8.5 lbs. SR762 weighs out at 8.6 lbs.
A 20rd SR762 mag topped off with M80 ball weighs out at 1.4 lbs. A 20rd M14 mag loaded the same weighs out at 1.5 lbs.
So...... both of them weigh the same.
SAI M1A's sporting 16 or 18 inch factory bbls are all non chrome lined. The SR762 factory bbl is chrome lined.
SAI's customer service is one of, if not the best around in my opinion. If you get a lemon, they will make it right.
Both rifles are designed to be used in the field, and not strictly from a bench. No bedding to worry about (M1A), or free floating handguards either. (SR)
I have 18in bbl M1A's with problem free rd counts of over 5000 easily. A well built rifle of this type will operate in just about any types of weather, climate, etc...etc....
Too early to tell how the SR762 will measure up, but I wont go back to DGI again, as it is one of the better built AR type rifles made for use in the field via it's design.
A new M1A (any model) sells typically with 1-10rd mag, while the SR762 sold with 3-20rd mags....among some other stuff.
Both rifles shoot well for use in the great outdoors.
Neither were designed to be "match" rifles either. Out of the box, both sport iron sights. ( SR762 sports Samson flip up irons.)
the SR762 sports a threaded muzzle with Ruger's useless flash hider on the end to protect the threads..... IE.....very easy to replace with another, a brake, or a can if you like.
You already know how your Socom's muzzle brake works.
The SR762 sports an adjustable gas system. Setting 0 shuts it off completley, just as your Socom's spindle valve in the closed position. Settings 1 thru 3 open it up more and more as you go thru the numbers thus allowing more ability to "tune" it per different load.
If your Socom II has the extended rail over the receiver, then it is as easy to mount optics as a flat top AR type such as the SR762. If not, mounting optics over the receiver require a scope mount.
Maintaining either rifle is easy. The SR762 requires less tools to do so, and it doesnt dump gunk into it's own chamber as the DGI types do, so it is much easier to clean compared to them. ( The piston is chrome plated so easy to clean.)
If it were me....... I would keep the Socom and save up for the SR. If that aint possible, sell the Socom, then buy the SR, as the Socom II is worth more than an SR762.
If your plan is to add a can, the SR762 is ready to rock outa the box. In addition, it is more compact than a factory produced M1A Socom, and the iron sights can be utilized with just about any type of can installed.
Hope this helps some.