I'm looking to purchase a GPS unit for use at home in the US and also on trips to Europe. I'm trying to decide between the Garmin Nuvi 370 and the Tom Tom GO 910. The Garmin is more expensive but smaller. Does anyone have any direct experience with either of these models to help me decide?

No, I have no direct experience but I'm about to spring for the Garmin 660 as an anniversary present for the DH.

This model is about the same size as the 330 but I think it's thinner. It also has a bigger screen and integrated traffic reporting.
I've read a bunch a reviews and overall the Garmin units seem to be rated higher than the Tom Tom.

In the end, you have to decide what features you want and what price you're comfortable with.

My kids gave me a Garmin nuvi 350 for Christmas . They included the maps of Europe. Since we are heading to Italy in a few weeks, I also purchased the language card. It is great the way it actually "speaks" the words you select.Since I am in real estate, I have used it several times already to find places I am not familiar with. It is very user friendly. I just set it up in the console of my car. I will carry it in my purse in Italy to find places while walking and directions while driving in Tuscany. I cannot praise it enough! I love it!

I also have the Garmin 350. It's easy to use, it's small enough to put in my purse and the screen is large enough for my old eyes.

I got the Garmin 330 for Christmas a year or so ago, and the prices have dropped considerably. I also purchased the European maps to go along with it.

Garmin is one of the leaders in the GPS industry. If I were to upgrade, I would go for one of the Nuvi versions simply because they are a little more compact.

Can't speak to the TomTom as I've never used one, but I can vouch for the Garmin.