Micetic - do you anticipate wearing the inflatable at all times, or is it for emergency use only?
If you are going to wear it all the time, you have to go with an inflatable or a vest - if you are in a dingy, most sailors use vests like http://www.layline.com/prodinfo.asp?number=ESRA
which are designed to be worn with comfort. If you are not in a dingy, you can go with an inflatable.
if its for emergency use only, buy the best type I http://www.westmarine.com/webapp/wcs...roductId=13096
and equip it with a whistle, light and mirror.