I'm no expert on the gutter vac's or any of the kits/systems mentioned, but ive just put myself together a kit.
Got given this companies details -
http://www.carbonfibretubes.co.uk/about.html#contactGot 5, 2m/50mm tubes from them, cheaper than any gutter cleaning supplier. Carbon, modular and cheap.
Got a wetvac from Kev Martin on the hard floor section of this site. triple motor, 3000w.
Got all my other bits and bobs from ebay. Bend, nozzles, clamps, wireless camera etc..
Got 7.5m of 51mm vac hose and some cuffs from polarbrite.
All in it was just under a grand.
you can probably get a kit already put together for cheaper, but the skyvac kits are over a grand, and the ones under a grand, i just wasnt sure about the vacs.
I already have a generator, so keep that in mind as an extra cost if you dont already own one.
Check this thread out for links -
http://www.cleanitup.co.uk/smf/index.php?topic=177709.0