Hi, Just would like to ask what tube length I should opt for? The Rambone is offered with 34/39/43" inches. My draw from my fist to the corner of my mouth is 30". Its unlikely I will do any drawing past my ear. I have seen I don't want to stretch further than a multiple of 4.5-5 times the band length. Just a rough pointer will be fab. I'm aware there is a fair amount of trail and error but this is just to get me off the block. Thanks.