After reading a number of post on this site I have decided to purchase a Garmin Unvi 275T for our trip to Ireland. Are there any other accessories I should purchase for the unit ?
You won't need anything other than what you get with the GPS - the cord and the window mount. I keep mine in a small generic camera case that I bought at Target when I'm not using it. The cases you can buy for it are too expensive for me. :)
If you decide to go ahead and get the sandbag for the dash, have it out with your electronics when you go through security. Mine apparently looked suspicious on x-ray and caused me to get my bag searched. Mind you this was at JFK. I will do my best NEVER to route through JFK again. They are very inefficient in their security areas.
Beware of mounting a GPS on your windshield. When you remove it and hide it away while you are parked somewhere you can still see the tell-tale mark on the windshield. It is not unusual for people to have their car broken into because someone is looking for the GPS. That applies here in the U.S. too.
That's why I always wipe the windshield when I remove it. :)