First off, I must stress that these are my own opinions, and should not be taken as fact. Secondly, do not expect comments about particular classes or teachers, positive or negative. This would be unfair, and I am sure that more than one WU staff member visits this site.
Without further ado...
I started attending Webster University's St. Louis USA campus (www.webster.edu) in 2002. I have remained a member of that campus, and only came to the WUT campus (www.webster.ac.th) as a study abroad student. However, this fact has more to do with paperwork than experience, as I went to the same classes as regular WUT students.
WUT is essentially an American University in Thailand, and all classes are taught in English. There is an extensive ESL program for those wishing to enroll but lacking in the English language abilities.
I cannot compare the quality of my education at WUT to another Thai university. When compared to similar courses at the St. Louis campus, I found them to be a bit easier. This did not suprise me, seeing as how so many people are still mastering English. In that sense, I had a bit of an advantage.
The Thailand campus is also lacking in supplies. The last time I attended (2004), class textbooks still took 4 to 6 weeks to arrive, if they arrived at all. While cheap by American standards, the price of textbooks was high. Computer labs were not of very good quality and the internet is slow, although I believe that this has improved somewhat over the last year.
In terms of education, I think that you will get out what you put in. If you work hard, study, and become involved, attending WUT should be little different than any other university. The campus is small, but we are a pretty tightly knit group in general. I have a great deal of positive experiences from this campus, which is why I will be finishing my last semester there this spring (Graduating with a combined degree in Media Communications).
If you are seriously interested, you can visit the campus. I don't think you need an appointment to do this, but if you schedule one a person may be there to show you around.
I don't mind answering any further questions, but please visit the campus website before sending me anything. Also, I would be interested in knowing your opinions about Webster Students in Hua Hin. Are we a fun group, or do we piss you off? I imagine its a little of both.

Congrats on the 3 years HHAD! Keep up the good work!