I think it really depends on what you want the rifle for. Others have said that before me and to use the new buzz term “the mission drives the gear.”
If you want a rifle that will deliver good accuracy, is absolutely beautiful to behold, has historical significance, and that you can shoot service rifle matches with, a nice National Match rifle would be the way to go. You would be looking at about $2000+ and would have the issues associated with a glass bedded rifle. One thing I would recommend is look for an older M14 that has mostly GI parts on it. As others mentioned, after about Y2K, SAI started using more and more commercial parts and some of these (but not all) have dubious reputations. Most rifles people buy are really safe queens and even if the bedding is loose, it is way cheaper to have the bedding repaired (skim bedding) than it would be to replace the bolt group and operating rod with GI parts. Even if you find an older rack grade rifle with GI parts, it might be cheaper in the long run to buy that rifle and have it match conditioned. A rack grade M14 should be about a 2-3 MOA gun.
If on the other hand you want to build rifle on a modern stock platform I wouldn’t waste my money on a New Match gun (no use in paying for bedding if you don’t use it). If you are wanting a 20 inch platform, get yourself one of SAI’s “Loaded” rifles which includes a 20" Krieger barrel, match sights, and some other upgrades. Or find yourself a nice used rack grade rifle. Keep in mind that you will still not have a match gas system so there is still some room for improvement. This should run you a little under $1500 and then you can drop it into the JAE or TROY stock. If you go this route, your rifle really won’t require any more maintenance than would an AR type rifle. The problem you will have is that the M14 is still a lot harder to “gunsmith” than an AR platform is, so things like barrel replacements, bolt swaps, and the like will most likely require you to take it to a gunsmith who is familiar with the platform.
If you want a shorter barrel, then you are looking at the “Scout” or the Socom rifles. The Scout is what Springfield used to call the “Bush” and has a 18" barrel. To my knowledge, none were ever offered from the factory with match grade barrels. Both the Scouts and Socoms are newer rifles and as a result will have mostly commercial parts on them. All Socoms and the “Squad Scout” have forward optic mounts for scout scopes. If you can find a used Bush rifle, this might be the best option as you will have more GI parts.
On receivers, the LRB receivers are nice and closer to GI spec (but still not a true “forged” receiver) but I really have not heard of too many issues with SAI cast receivers falling apart on their owners. There have been some issues with dimensional tolerances on the SAI receivers that can come up when mounting 3 point scope mounts such as the ARMS#18. I would rather save my money on the receiver and spend it in other places (GI parts, stock, etc), but that is me.
On commercial parts, there is a lot of debate about them going on (just like on the AR15 platform). The general agreement is that GI spec parts are better, but the problem is that they stopped making them years ago, Klinton chopped up thousands of M14s, and the Military is now hogging up all the M14 parts they can get. This is making the parts more and more expensive for the civilian market, thus there may be no alternative to commercial parts in some areas. Just like with ARs, if you have a rifle with commercial parts, consider upgraded them as you go. One good thing, if you buy a SAI rifle, they will repair any parts that break for free - but that will not be any comfort when your op rod breaks when the goblins are at the door.
Oh well, I have babbled enough. Hope my thoughts helped a little, like I say, I have been a fan of the 14 for years and have been studying it, but there is so much I don’t know about it. m14tfl.com is to the M14 what M4carbine.net is to the AR. Go there and your head will explode with information. Also, should you pick up an M14, get yourself Scott Duff’s “M14 Owners Guide” - this is an excellent book and will help you understand and maintain your rifle (it also made me realize how much I don’t know).