me thinks that A3/4 prints from inkjets are nice. i find my A4 prints colours and everything nicer than those i have printed from labs. i did around 8 prints (8R) from fotohub during thier promotion and find it kinda inferior to those printed on my inkjet. Canon S820.
if i remember correctly, i have seen megaweb's insect A3 prints some years ago using someone's Canon A3 printer and they look darn good!