Cutting Mobile Phone Costs

I'm with O2 but make the vast majority of my calls to Vodafone. Should I switch to Vodafone or try one of the O2 tarriffs? I've looked at www.callcosts.ie and the O2 Active Life plans look ok but do they include line rental? - Active Life 150 gives 150 free minutes, 100 free txts and charges additional calls at 30c per min. All this for €50.

Any other options I should be looking at?

on 3 in get 300 minutes to all landlines and mobile sin ireland and 300 text messages also for €60, its great my bill is never more than 70. I was with 02 before and i could never use my mobile that much and have a small bill like that.