Tire Chain Requirements for 2007?

We are in the middle of a trip to/from the midwest from sunny California and decided to pick up a set of tire chains for our 2007 model. Our Toyota dealer indicated that this year requires a different set of chains due to the inflation sensors in the tires. We waited until last minute to check in to this and ended up going with the set the dealer recommended. The prices was over $60.

I'd like to know whether others have been told this and/or what your experiences have been? With luck, we won't have to use them and I'd consider returning them if there is a good & cheaper alternative out there.

This is our longest trip in the prius and it's working like a dream and our trip average so far is 51-52 mpg for the 2200 miles of this trip depending how hard the wind is blowing.

Thanks, Dale