Hmm. yea interesting. I hope you're not just limiting it to Neptune's but would potentially host any mining gear.
That aside, to help decide whether it stacks up here are two points:
1) If you've got an EU VAT number (i.e. you're trading as a business or know someone who is) you can buy within Europe and KnC don't have to charge you VAT, so in practice it's like being in the USA as far as taxes are concerned.
2) Best commercial hosting quote in Europe I've found so far is $180 per kilowatt per month including power. So that's probably going to be around $550 for a 3Kw (guess) Neptune.
If you can beat that then I'm interested.