With pretty much everything in my favour (no mods, paid in one go, great postcode, 2 yr ncb, no accidents or claims, no points/convictions, use of other cars, limited mileage, 3 named drivers) I paid £1450 at 19 years of age in march last year for a FF 182 fully comp.
It would have been £1320 for a normal 182 (Long story short you are legally obliged to declare optional extras, and Bell charged me £130 for the pleasure of factory fitted spoiler/lowered suspension)
I found, certainly with Bell/admiral/etc that a 182 was cheaper to insure than a 172. I guess they figure (and reasonably) that someone will take more care over a 3.5k car than a 2k car.
P.S.
http://www.cliosport.net/forum/showthread.php?410729-Insurance-thread-for-young-1*2-owners