Mini Pro by far, the type feature on the mini is very unsuitable for a small phone and the actual qwerty keyboard on my Mini Pro is perfect, its one of the reasons i did not buy HTC... They are roughly the same price anyway. I got a Mini for my brother first, I liked the Mini so much and really wanted to buy the Mini but then the Mini Pro just came out and opted to wait for the price drop of the Mini Pro, after 2-3 weeks i paid the same price for the Mini Pro as I did for the Mini I bought for my brother. I have acess to both phones and think the Mini Pro is a much better option, another plus side is that Mini Pro's screen also has the hardware to support multi-touch which we currently do not have but may well be cracked by Owain very soon!
PS. Mini Pro is perfect for emulators such as Nesoid, Snesoid as you can configure button inputs and do not have to rely on onscreen touch buttons which will not work on Mini anyway as it will not support the multi-touch.