Which carrier for official tethering?
 

I just moved to Holland from Finland. I have a factory-unlocked iPhone 4 and an iPad, and I want to get a contract at least for the iPhone. As I'm an iOS dev, I'm using iOS 4.3 with the Personal Hotspot feature, so I think that could cover my needs with the iPad, at least for now.

The question is, which carrier to go for. On Apple's support article, they list three carriers for the Netherlands: KPN, T-Mobile and Vodafone. Only Vodafone is listed as offering tethering. But when I visited a phone store, the sales clerck told me that no carrier in the Netherlands officially provides tethering. Which one to believe?

Another thing is that if those three are the ones supported by Apple, they get the settings (APN,...] distributed automatically, while for an 'unofficial' carrier, you just need to enter them manually. This is not a problem, if it would also give me tethering. In that case I would be happy to use a carrier not officially supported by Apple.

So, recommendations on which carrier to go for are highly appreciated. Other than a data package (preferably at least 1GB, preferably not capped to less than 1 Mbps), I need some very basic package, I think 100 mins + 50 SMSs would do.

Another thing is that I have my own company (a sole proprietorship), and business plans could therefore be an option, although I would prefer a private contract.

And if tethering is impossible to get for the iPhone, then I might get a contract for the iPad as well. For that, I can see the offerings on Apple's site (T-Mobile 10€ for 200MB, 30€ for 2GB; Vodafone 20€ for 500MB, 30€ for 2GB), but any additional tips are also welcome.