Sucks you had to leave Hawaii! I feel for you man.
About the kites, the rhino 06 has lotÃƒâ€šÃ‚Â´s of battens and things and i can only imagine the 20 would pack down huge. It is not the most stable kite, you are an advance rider so you shouldnÃƒâ€šÃ‚Â´t have any problems, but the conditions you mention might not be friendly to a higher aspect kite like that. I have ridden a 12m 06 in medium to powered conditions and it is a nice kite, really doesnÃƒâ€šÃ‚Â´t feel any different to the Spitfire III.
The machine 20.5 i tried was a pig! Slow to turn, no power, complicated system, wear on the bar parts, not easy to relaunch, huge leading edge and struts (lotÃƒâ€šÃ‚Â´s of pumping) and also big battens and big packdown. I have never flown the 17.5. The time i flew the 20.5 i immediately went back to my Caution Spitfire II 16m and had a bit less power but a lot more fun, much faster turning, response, and ability to do some tricks!
I have an answer 16m and it is a sweet kite, very fast, great for waveriding, i have had no issues with stability, but you have to watch where you put it in very very light winds on the edge of the window close to the ground. I think the Spitfire III 16m which i also owned had more power, and is more stable, user friendly. You can just park the spitfire, pull the bar in and get the power.
Sooooo, what does all this come to, i am sure the 20m Spitfire III is a great kite, i have used the Spitifire I and II 20meters and it is a great kite, lotÃƒâ€šÃ‚Â´s of power, fast turning, solid, uncomplicated. The Spitfires III were faster, with slimmer struts, and safer and more stable with the 5th line. I was just in San Diego last weekend and the guys at http://www.calikites.com
have a cheap Spit III 20m i think, and they are also cheap on http://cautionkites.biz.sco.com/?mainUR ... _id%3D5x3h
although it says out of stock. They also have the answer1 16m cheap http://cautionkites.biz.sco.com/?mainUR ... _id%3D5x3h
but i think it is without bar.