By default my "automatic" network selection keeps picking pu Meteor (Edge). Should I leave it at this or should I switch to manual and pick O2 - IRL 3G (or 2G) one of the other networks.

Anyone out there have an opinion on which network to use while in Limerick?

Meteor does not support blackberry. Only vodafone and O2 in Ireland support Blackberry. I'd recommend O2.