A few months ago I bought a Kinesis Freestyle keyboard. I can’t recommend it enough, I can’t use anything else, and believe you me, I’ve tried most of the brands and types available, and this is by far the best keyboard I’ve tried (Kinesis other lines are also great, but this one suits me better).
I have the Freestyle VIP, I use it detached, as I prefer the separation, it does take a while to get used to, but your hands will thank you for it. The tactile response is really good (this varies from person to person, so what works for me might not work for you). The keys emit a click when pressed, like a mechanical keyboards, it’s not as loud as the IBM keyboards, but it’s good enough for me (I favor the click sound).
Kinesis support is top notch! A few days ago I broke a couple of key caps cleaning the keyboard, I emailed tech support for information on how/where to buy replacements keys, and they mailed the replacements for free to me! That’s what I call service, it’s true that I only needed two key caps, but most of the other companies I’ve dealt with, wont do this, they will sell you the whole batch of keys, which in this case I would have gladly bought, but it’s kind of a waste to buy the whole batch when you only need two or three keys, so I thank them for their support, I’m a happy customer (not only for this, but they always answer promptly, to email enquiries).
I recommend buying their keyboards, I bought mine direct, and it was a pleasure to deal with their sales representatives, as well as their support staff.
Thanks again to Kinesis for a great product, at a reasonable price, with amazing support to back it up, also they have a version for the Mac, with all the mappings needed for the OS.