Does anyone have any experience with these shelters? There's the 949 and the 949i I'm eying. My specific question is is there a huge difference in insulation? I don't need it to be super insulated, I just don't want to buy the regular one to find out it's like swiss cheese keeping the wind out. I currently use an uninsulated KillZone and that's fine.. just too small. Is the uninsulated 949 good enough on it own right?