Honestly, the only way you'll know is if you pick one up and play it.

The MiM strats are well made instruments, but there are difference in the hardware. When/if you compare, use the tuners, look at the nut material (and US Strat will have a bone nut), examine the frets, feel the neck.

When I compared them back in 2000, I decided on a US made strat. The neck felt smoother to me and the tuners felt more solid. Overall, the guitar just felt more solid to me. I've played that guitar almost exclusively since then and (knock on wood) I have had no trouble with it.