Paddyboy -
I can only give you my opinion based off my own experience with a Shoei TZ-R, one of the "mid-range" Shoei helmets. I'm a new rider (1 year), and when I went to buy my first helmet, I did plenty of research on websites and at stores by fitting them on my head and checking weight, visibility, comfort, etc.
www.webbikeworld.com is a great resource and has a vast number of reviews that I looked at as well, including Shoei TZ-R, RF-1000, etc.
I personally love my helmet. I ride a 2007 Bonnie, so the sport helmet is a little off-kilter when it comes to the whole "look." But, after trying multiple helmets on, including HJC, Arai, Icon, Shoei, Scorpion, the Shoei fit my head the best. I have a smaller noggin though, and relatively oval. As I'm sure you know, each manufacturer has different 'inside' shapes to their helmets, and some, like Arai, fit more oval heads better.
Without getting too long-winded, I wanted a helmet that fit snug and secure, reduced wind noise well, and had plenty of venting so my head didn't cook like an egg. The TZ-R did all of these VERY well. Unfortunately, Shoei are a little more on the expensive side. But, I can honestly say the money is well worth it for the comfort and fit, as well as being safe (both DOT and Snell approved).