Hey guys, I'm one of the co-owners of Vibe Kayaks and would be happy to answer any questions you might have.
Neumie, looks like you're right the KI-3 is definitely the same mold that we've licensed but there are some major differences. We visit our factory several times a year to make improvements to our kayaks and accessories and to make sure quality measures are being met. That said, some of the major differences we made to our Sea Ghost 130 are:
1 - Material - All Vibe Kayaks are high density polyethylene. The KI-3's are more than likely linear low density polyethylene. LLDPE is fine for the beginner budget paddler but it's much easier to scar and wears out much quicker. We paddle around oysters and rocks way too much to use LLDPE so we send high density raw material to our factory instead of using their standard LLDPE material.
2 - Rudder System - The Sea Ghost 130 foot pegs are clipped to nylon rails that slide freely inside of aluminum tracks. The foot pegs can be quickly adjusted while on the go and the aluminum tracks makes the rudder controls smooth as butter. We had those custom made since we don't like plastic-on-plastic rudder controls. When comparing similar models, you'll want to make sure the rudder cables aren't just tied to the foot pegs. The problem there is that you can't easily adjust the foot pegs for different leg lengths and the plastic foot pegs can bind in the plastic rails after a few uses.
3 - Warranty - We believe in our improvements and quality control measures and offer limited lifetime warranties on all Vibe Kayaks! Warranty
4 - HIN - All kayaks from Vibe Kayaks have a HIN (hull identification number) and MSO (manufacturer statement of origin) so you can register your boat, put a trolling a motor it (if your state requires registration for motors) or own it legally (some states require HIN's for any water vessel).
There are a few other minor differences with hatches, handles, seats, etc. but these are the biggies that I could think of.
Any other questions, feel free to gimme a shout!
Tight lines everyone!