To mummy or not to mummy?

I made a trip to the sporting goods store for camping supplies this weekend and left more than a little overwhelmed.  Who knew there were so many types of sleeping bags?!  I believe the last sleeping bag I owned the only decision I had to make was what character was on the front and now not only is there the color decision, but also the weight, the size, the cost, the temperature, do I want to be a mummy or the regular version?  And to be honest the whole mummy idea freaks me out a little bit.  I'm the kind of person who takes up the entire bed when given the chance (I'm single so it's allowed) and I'm not sure that being in a mummy position is not going to make me feel more than a little claustrophobic all night long.  I like to be able to move and stretch out or at the very least have enough room to reach down and scratch my foot at night if needed.  So I left the store empty handed except for the camping pillow and bug spray I'm suppose to soak my clothes in to keep the critters away.  I guess I will be doing some more research before I return to the store and hopefully will leave triumphant and happy with my new purchase the next time.