I have the latest version of Maps, from April 25th 2012.
I do not have any special setting for highways or toll roads, I'm using the default to allow them.
I've noticed this a few times but only recently did I really pay attention. I decided to use Navigation for a approx. 20 minute trip, where I already knew the quickest route (it didn't use highways or tolls, just main roads).
The route that Maps selected was a 30 minute trip, using a highway to circle my city. When I selected to see alternate routes, it showed two more, one of which was close to my intended path (estimated at 17 minutes).
So the first problem was the fastest, simplest path was not the first selected (shouldn't it be?).
The next problem - even this route wasn't the fastest, I was told to get off the main road miles in advance. I decided not to, to which Navigation started recommending that I make a U-turn.
It continued to recommend U-Turns up until I was literally within eye-site of my final destination. At that point it was about a minute's drive.
There was average traffic, my route ended up being faster than the provided ones, and Navigation pretty much provided me an entirely useless experience. This is unusual. Usually it's great.
Has anyone else had similar problems?