My parents are very kindly buying me a bell tent for my 40th but I don't know whether to go for a 3 or 4m. I am taking it to a festival next weekend so would have to lug it between car and campsite, so weight is a consideration. I am a single parent to 2.9 year old DS so need to be able to manage it on my own. The 3m looks more sensible but I think I'll get more long term use out of the 4m. Does anyone have any advice? Thanks!