If you are going to open a shop in Dublin there is little point in putting it on the outskirts. Yes, you might get a few people who live/work locally and others who are willing to drive to you, but for the rest of us, getting out to Lucan, or Sandyford, or wherever seems like a lot of trouble. Much easier just to get the stuff delivered, thus making the shop pointless.
The advantage of a shop in Dublin would be to allow people to drop in and have a look around and that is more likely to happen close to town. The Smithfield location looks like a very good compromise. It is very close to town and has good public transport links but the rents should be relatively low, as there are a lot of empty units there.
[size=59:2zyon0rt]The fact that it's a 10 minute walk from my house is also a plus. [/size:2zyon0rt]