I have 6 kites, but really only use 3, as I've updated, and my younger brother is about to get into kiting, so he will probably buy my old stuff to get into the sport cheaply. I used to use my '05 Gaasta Visions (8m, 12m & 16m) this was a pretty good quiver of kites, but I have since upgraded to '06 kites, 7m Switchblade for really windy conditions (25Kts+), 12m Liquid Force Menace and 16.5m Cabrhina Contra. I prefer the feel and handling of a C kite, but got the SB for the ability to handle gusts in higher winds. I prefer to ride flat water to small waves (Haven't gotten into the surf scene a whole lot yet, but looking at doing more of that next season when I am home in WA).
I own 5 boards, two Underground FLXs, both '05s. Absolutely LOVE these boards (128 & 142). I also have an older ('04) Naish Mutant, an Underground 5'5" Surf-style quad-fin directional with straps. I also have a 158 Cabrhina prodigy.
I use a Pro-limit Harness, but still prefer my old Gaastra Harness that spectacularly tore a strap after a justifiable amount of abuse ;)
I've recently bought an MBS Landboard too, but haven't really been able to get out on this yet (I've only had it a week and the wind here in the US is........ well c**p to put it nicely.
I am 6'2" and currently weigh about 95kgs and find the 12m LF good in about 15-25Kts, the 16.5 is good on the 'boat' (158) from about 10-11 Kts up to about 20 on a smaller board. the SB turns like a terrier puppy on crack and is as twitchy as one too (because of the small size, but when I take it out 25+Kts I don't usually need to move it much unless jumping).
Personally my fav size is a 12m and has been since I started with my 12m Vision (I was 85Kgs then) and riding either the 128 or 142FLX.

D