Adjustable airbag suspension

I have been looking at airbag suspension kits. I was wondering what companies I should look at? Also does anyone have airbags and is it worth it?

Thanks,
Fil

http://www.dejayssaleen.com/videos/airride.wmv
http://saleenpower.com/forums/index.php?showtopic=572&hl=
http://saleenpower.com/forums/index.php?showtopic=1462&hl=
http://www.ridetech.com/
http://www.dejayssaleen.com/Mar26/2.jpg

With airbags can you adjust to specific hieghts or is it just stock then a 5 inch drop. How much did the whole thing cost minus labor, was everthing included in one kit? or is it four kits one for each tire? By the way that was a pretty cool video.

Fil

i have no idea how much it costs im assuming the pricing is on the site and you can adjust it freely he just went all the way up then all the way down for effect.