I have tried many, perhaps all, of the iOS & Mac OS X remote desktop clients of which Im aware. (I look anew from time to time.) I have spent almost two thousand dollars for such software over the years. I routinely use Remoter VNC (mostly from my iPhone, but occasionally from an iPad) to access Macs from cellular data connection (including fast moving cars (while others are driving!) and 3G settings) and random WiFi settings. I am able to rapidly access a desktop, take actions (some very complex) and disconnect with assurance. I dont recall being disappointed or surprised. I have used Remoter VNC for 5+ years across many, many versions. I find the keyboard UI good-to-great and the pointer control excellent. The SSH Tunnel works well. I have a very strong technical background, do some development and tend to very picky and critical, but I cant really think of any issues. I recommend Remoter VNC to anyone remotely accessing Macs. (I dont talk to many folks that use PC. :-)
Steve_.W about Remoter VNC - Remote Desktop, v4.8.03