I took the plunge recently and bought my first mechanical keyboard, the Das Keyboard Ultimate. It was very hard to find someone that would ship one to NZ, but eventually I found AusPCMarket that ships the Das as well as several other "clicky keyboards". The Das is known for being a bit pricey.. the Ultimate set me back $230NZD (incl shipping and GST) at the current exchange rate and was delivered in just over a week. If you need to justify the price by thinking of it as an investment, then do :)
With it being my first mechanical keyboard I'm unable to give a fair review in comparison to others of its kind. My previous keyboard was a Microsoft Comfort Curve 2000 keyboard (a much cheaper $40NZD), a brilliant keyboard but of course based around rubber dome technology.
Anyway, it took me a while to adjust to the non-curved layout of the Das, but now that I have I feel that I am touch-typing much MUCH more efficiently than before. It feels great to type on, plus it sounds amazing! Personally I revel in the sound of the Das, and while I wouldn't want to use one around sleeping people, it certainly won't break through any music playing on your headphones and so far doesn't seem to penetrate walls ;)
Overall a definite thumbs-up from me. If you're in NZ and looking to get a Das, I'd highly recommend also going through AusPCMarket as their service was quick and no-bullshit.
Since posting this MightyApe.co.nz has become an official Das Keyboard stockist, so NZers can save a few bucks by grabbing it from there. I also managed to pour coffee through my Das very shortly after getting it, but after flushing it out with water it is still clicking away like nothing ever happened, WIN!.