I don't think Andy has been that bad this week. He had a momentary blip against Millman and sorted it out. He was pretty good against Istomin, and knee or not I think he would have more or less walked over Nishikori. Again, he appeared to wobble at the start there, but he sorted it by winning five games on the trot. As someone in the crowd at the USO said when Andy was playing Cilic, it's not how you start, it's how you finish, and Andy isn't finished yet in Brisbane.
I think Andy is looking good ahead of the AO. Sure, there are some improvements to be made, but that is the purpose of these warm up tournaments. I wouldn't want to see him playing a blinder in Brisbane to then be average in Melbourne.
On balance I like Dimitrov's game. He's definitely got something about him. That said, I don't think he moves quite as well as Andy (frankly, not many do now). I'm also not altogether convinced that he always has a plan B available when plan A isn't going so well, at least he hasn't when I've watched him.
If Andy comes out flying from the off I reckon he could do it in straights. However, in reality I think he'll do it in three.
Forgot to say, Dimitrov is a bit pretty, which sort of helps, but I'm not taken in by such things lol.