Have told the staff for years now that they should remove wire from bonsai and they still do not. Wire is left on and it cuts into the bark reducing the health and value of the bonsai. If some one buys such a bonsai it is because they do not know better.
Waterloo is one of the premier Garden shops/nurseries in the area. They have two locations: the original one in Devon (next to the Horse Show complex), and in Exton (with a lot more space). The sell a mix of plants they purchase (larger plants, shrubs and trees) and stuff they grow themselves at Exton (in the back). Extensive greenhouses, foliage plants, pottery, orchids, bulbs, wreaths, real and artificial flower arrangements, china, bird feeders, etc.
They also have a very extensive Garden Shop with everything from Patio furniture to Christmas decorations to general decorations to stuff for the garden (fountains, stonework, etc).
They also do design and build landscaping, and usually win awards at the Philadelphia Flower Show.
They're not always the cheapest place, but they tend to have a great selection, excellent quality, cheap delivery, knowledgeable staff, good sales (in the paper every week), and they have excellent an warranty policy.