Hi, I agree with Kim about checking out the disboard forums. When the ME service first started there were some complaints, but now that all the kinks are worked out, I hear mostly positive things about it.
I will actually be using Magical Express for the first time next week, as DH and I are leaving California for a two week honeymoon at WDW, woo hoo! We were actually married last year, so Oct. 14 will be our first anniversary, but this is also our official honeymoon. I always tease DH in saying that I've been planning this trip for probably the last 15 years...(we've only known each other for 10 years!)
One other thing about Magical Express. I haven't decided whether or not to pick up our own luggage and take it with us, call me paranoid, though I have read lots of postings on disboard by people with positive experiences regarding having their luggage picked up and delivered to their room. I think either way would probably be fine, but if I tag my luggage for pick up by them, I will at least pack stuff for the first day in my carry-on.