I have tried all kinds of touch phones except one running on android. Starting with the terrible nokia 5800 to n97 to iphone I had used it all so when I was getting my first android I was sure I wanted a physical QWERTY. I like texting a lot and I thought that when it comes to a new phone I wanted texting to be easy. With all this in mind i bought the htc desire z. It was a mistake! No, not because it is not a good phone, which it is but because of two reasons:
1. The bulk that a full QWERTY adds to a device is substantial and one should really consider that, and;
2. Because, android keyboard along with the excellent add on such as swype and swiftkey x makes typing in touch a child's play.
I now rarely use the full QWERTY and end up using it at times only when I feel that I should use it as opposed to needing to use it. Hence in gist, it is not a good idea to get a physical qwerty if you are using an android. Because, chances are you will be cursing yourself like I am cursing myself today.