Going to W&L was the best decision I have made. As you have read, it certainly is not the right school for everyone. It is true that the social scene is dominated by Greek Life (something like 92% pledge) but that is not necessarily a negative. In high school, I did not picture myself as the "fratty" type per se. What is great about Washington and Lee is that all parties are open (except some mixers and formals) and even if you didn't think you would want to go greek, you will be able to easily find a good group of guys/girls who you really get along with.
That being said, there are other social outlets; we have singing groups, intramural sports, bands, community service groups etc which one can get involved in. The trick is to find a group of friends and get involved with them.
Academically W&L is great. It is challenging, but not to the point where you cannot have a social life and maintain decent grades. The professors are incredibly knowledgeable, and also extremely helpful. They are always willing to meet with you or give you feedback, you just have to approach them; they won't hold you hand.
My one complaint would be that the school's AP policy kind of sucks, don't expect much credit for classes unless you got 5s on your tests.
As far as the school's reputation is concerned, it is true that it is not "well known," to the generally public anyway. Anyone in academia or anyone at top corporations will have heard of it, don't let that stupid towny from wherever you live deter you because he hasn't heard of it. W&L will be able to provide you with any opportunities a big school can (minus a football stadium of 45k). There is a very strong alumni network and ample opportunities for internships, study abroad etc. Not to mention the people that you meet at school as prestigious as this one will be able to offer you additional connections to their parent's companies and whatnot.
Of course, you cannot have a review of Washington and Lee without mentioning the honor code. Many school's brag of having a great honor system, but none implement it quite the same way as W&L . Our school embraces the honor system, and the affects on the students can be seen everyday. We have un-proctored tests, we schedule our own finals, we leave our laptops everywhere, we don't lock our doors, and the list goes on.
In reality, you have to come to your own conclusions about the school. I highly recommend doing an overnight, but make sure you go out and experience the night life (so come on wednesday, friday or saturday). Most people I have talked to said it just "felt" right when they visited, so make sure you get there!