Couple of things--
There are no more "short" WB Chrysler vans. The 2008 redesign eliminated them.
The Town and Country is identical to the Grand Caravan. At the base level, there are no more additional features in a T&C compared to a GC--except a few interior trim pieces (the TC has fake wood and a fancy looking analog clock.)
I have reservations with
Avis, Dollar and now Alamo. Just made the Alamo one--it went WAY down for my trip which starts in a little over a week and now is less than the other two. I am very pleased--I like choice. In particular, I'd like to snag an 8 passenger Sienna. Plus, the Sienna's just a better vehicle. Every Sienna has a 3.5L 268 HP V6, compared to the Dodge/Chrysler's anemic 3.3L 190.
We own an 07 Odyssey, and my dad drives a 09 TC Touring, so I know my vans...
One thing that has me confused--Alamo/National used to have a separate category for 8 passenger vans--which means you could basically just reserve a Sienna. Seems to have disappeared.