I think it's good. I buy Carlow's stout and ales in Aldi for €1.79, they cost €3 in the craft beer offy in Maynooth. I'd love to buy more craft beer from them but sometimes I really can't justify the price, especially when the bigger craft beer offys in Dublin do decent deals all the time (although the Maynooth one is starting to do 4for€10 deals now).
There might be a certain romanticism with going to an independent off license and chatting with the staff about the beer but if I'm just looking to buy some of my usual favourites I'm going to look for the cheapest price.
As others said too, it can be a nightmare finding craft beer if you don't live in one of the big towns/cities.
People are always discussing the Superquinn beer offers, is Tesco much different?