Hi Deansocial,
Don't buy it!
I've got one and it's more hassle than it's worth.
a) there's a filter in the top that becomes completely clogged in a couple of minutes if you use it for sanding or hoovering dust.
b) if you use it for collecting chippings from an electric hand planer; it will only fill the bottom 20% of the bucket before the suction drops off.
My recomendation is to save your money for a Dust Deputy or if you feel like a mini project check out Sturdee's homemade cyclone
http://www.woodworkforums.com/f200/sturdees-tritons-dustbucket-mini-cyclone-17427/
Cheers
Kieran