Re: are all new 700 actions equal???
I'd hop on it, but plan on a new stock and barrel pretty quick. Is it a SPS or a SPS-Varmint? The Varmint barrel you could probably keep but the SPS is very lightweight.
I had a SPS I picked up as a similar deal several years ago. I tried everything to get it to shoot better than 1.5". Free floated, bedded the stock, trimmed the barrel down, recrowned it, even stiffened the stock with carbon fiber rods to get it to stay free-floated on a bipod. I finally rebarreled it and dropped it in a B&C stock, then it shot about 3/4" @100yd.
But to answer your original question, the actions appear to be the same. They may have additional quality control on higher end actions, but I didn't see any evidence of low QC or other problems with my SPS.