Being an SE owner, I wouldn't say they are over priced and you are getting a very high quality instrument for your money and as you will see from these boards many of the American made PRS owners rate the SE editions very highly as well.
With musical instruments, I am a firm believer that you get what you pay for the large majority of the time and the SE models are VERY popular, even more so than Fender as a whole these days probably..... If the SE models were crap, they wouldn't sell. It's as simple as that.
However, to refer back to the original question of why should you buy an SE Custom 24 when the price is so close to an American Strat? Well the real answer is that it shouldn't even be an option because they as mentioned before, they are completely different guitars with very different sounds and if your main considerations as to why you should buy a guitar is being based on brand name and manufacturing country, then you have missed the point in a big bad way.
Go try one, you won't regret it.