The way I built my match rifle I would do again.
A free floated barrel is a must. The smallest targets you shoot at are with a sling. My sight adjustments from standing to sitting to prone with a **TIGHT** sling are so small they can be ignored. Try that trick with an unfloated A1 barrel. ANOTHER EDIT: I think the A1 profile is the same aft of the sling as an A2?
I assembled it from parts - a DPMS match upper from Midway - I think they are on sale again, 450-500 bucks with bolt and stainless barrel.
I have not used an upper made by the custom shops, but I do not feel I am at a disadvantage equipment-wise against the best. The only misfeeds I have had with that rifle are when I misalign the cartridge when single loading. A chrome lined moly barrel necessary? I think not! Go to your local SR match and look what your non-novices are shooting. All stainless, all the way.
This comes with a 1/4, 1/2 minute match sight that I have no real complaints about. I'd druther have a straight 1/2, 1/2 minute sight.
I did buy a Jewell trigger from midway as well. This is pricey at 175 bucks or so, but MAN! It makes a difference. If I had an existing rifle, I would replace the trigger first of all.
The rest of the rifle I built up from cheap parts, as in as cheap as I could buy them.
I loaded the front with cuff weights, and balanced it out with 230 grain slugs in the buttstock.
Say what you want, but this rifle shoots like a dream.
I used my M1A Springfield Armory sling, but I since bought better ones made by Turner. A high quality 1907 sling by Turner or Tam is a must. Some guys use the web sling, but 90% use one of the 1907 slings. These cost about 35 bucks.