I've been using Enterprise car rentals for the past several years and have almost always been satisfied. During our recent visit to Calgary, we rented a car from Enterprise and my experience has been good.
The hotel that I stayed at was three or four blocks from this Enterprise location and they offered to pick us up for free. The pick up service could have been a little friendlier, the driver pulled up in front of the hotel and when we came out didn't even say hi or offer to help us load the bags.
Apart from that, the lady at the counter was amiable and quick. Returns were also simple. They even helped us call a cab to take us to the airport.