I only have the 1.0 Tog bag ... i just bought it the other day for summer, it depends on your house and whether or not you will be using airconditioning during summer, use the thermometer that comes with the bag in your room and it actually tells you what one to buy. But i dont think it is necessary to have to many.... ecspecially at that price!
I have found Joshua is still getting use to it as he is not use to his hands being exposed, it is so cute he still sleeps with his fists clentched and on his chest as if he is wrapped!
God love him!