For longer distance stuff I wouldn't recommend a messenger bag -you'll get too sweaty and uncomfortable with it, and panniers are a much better bet.
For Dublin-Galway or Dublin-Cork, it would only really be a one day trip (albeit a long one), but then I guess it depends if you want to do something when you get there, or is it just t he journey that's the fun part?
Dublin-Galway is basically flat, and 72" would be easily enough to get you there -the Cork route has a couple of hills which may be tricky (like the Vee), but ye should be ok
For longer distance stuff I wouldn't recommend a messenger bag -you'll get too sweaty and uncomfortable with it, and panniers are a much better bet.
For Dublin-Galway or Dublin-Cork, it would only really be a one day trip (albeit a long one), but then I guess it depends if you want to do something when you get there, or is it just t he journey that's the fun part?
Dublin-Galway is basically flat, and 72" would be easily enough to get you there -the Cork route has a couple of hills which may be tricky (like the Vee), but ye should be ok