You made a great choice!
We just recently purchased a 25FB and we love the floorplan, works great for how we live. Though that extra two feet of closet space you got sure would come in handy
We have had two trips and five nights so far and the Airstream is super!
For a TV, we ended up going with the 08 3/4T Chevy DuraMax/Allison and are VERY glad that we did! Truth is, for more experienced towers, a 1/2 ton would have been sufficient, BUT I really like have the extra power and strength. This baby tows like a dream, I honestly have to look in the rear view mirror to remember that I am towing it! Very cool! With your 27ft you'll be really happy with the 3/4T.
Make sure you get the sway control hitch! Very important. We have the Reece DualCam something, it is great, but longer models seem to really like the HaHa (Henly).
The other thing that you are already discovering about AirStreams is that you have not just purchased something to camp in, you are joining a wonderful community of people!
"FAST" (Friends with Air Stream Trailers) - I like it!