Britrover,
I have 12" apes and love them. The riding position fits me better than the original bars. I also have no problem turning or cornering.
The only thing to consider is you arm length. If you have short arms, it may not be as comfy.
At higher speeds you really lean instead of turn anyway. At corners I occasionally turn with only one hand. This isn't really an issue, more just preference.
You will however need longer cables and lengthen your wires.
I bought my bars on ebay for pretty cheap and had them powdercoated.
good luck
