I'm about to buy my first Life Jacket. The only three requirements that I have are that it is a "always on", that it is CASA certified and lastly that it is not too expensive.
T28D, pretty sure the one you keep banging on about (the sub $100 RFD one?) is about as compact as Jooliar's arse, does not appear to inflate, has no mention of any aviation certification (SOLAS is a maritime standard and is fine if you're fishing) and only meets the cheap requirement.
If I'm looking at the wrong one, can you chuck up a link?