I bought an MIM P-bass 3 days ago after playing an American Standard P-bass for 2 hours. The American version had different (maybe better) pickups, and I liked the headstock. Action, neck feel, weight, bridge, strings....I couldn't tell the difference. Both had the traditional P-bass growl.
After many visits to Mexico, I've concluded that there are many things they don't do well. However, they've been making outstanding acoustic 6-strings for HUNDREDS of years, and they take pride in their work. I saved 50% and went with the MIM, but I could be missing the finer points. Enlighten me, brothers !!