Generation differences
Yes, the differences in the various G-series Kribys have been extremely minor other than cosmetics. Here's a rundown of the functional (not purely cosmetic) improvements from one model to the next that I'm aware of:
G3=>G4: Improved Tech Drive
G4=>G5: Brush roll status light moved to the opposite side of the brush roll for no apparent reason; bag redesigned
G5=>G6: lower profile, rounded emptor introduced, supposedly less susceptible to impact damage; Micron filter bags introduced
G6=>Ultimate G: outer bag redesigned with curved zipper for easier access; rounded bag topper introduced
Ultimate G=>Ultimate G Diamond Edition: Two-speed switch introduced for this model only.
Ultimate G Diamond Edition =>Sentria: More ergonomic, lighter weight (and more fragile) handle design; LED headlight; improved brush roll introduced; optional delicate brush roll introduced; larger rubber bumper on the nozzle
Sentria=>Sentria 2: Mini emptor introduced offering improved air flow
Sentria 2=>Avalir: Improved shampoo system introduced. Handle redesigned, perhaps to save weight.
Other than that, my understanding is the 'guts' of a G3 are pretty much identical to those of an Avalir.
