I used to own an 04 YFZ and would never go back.
Ben, that isn't what you told me!?!

Haha, I keed.
I have had a little experience with all three machines discussed in this thread. I currently own an 04 yfz and love it. I know the machine well and have great success with it as far as power delivery and handling. The ride is a little hard and at the end of the day you get mad monkey butt if you don't have your seat repadded.
I rode an 06 TRX450 at the pismo dunes. I have nothing bad to say about them, especially this one since it was running a full IMS Roll design suspension (
$$$) and lots of other hop up parts. I don't know that I'd ever own one because I don't see it being the prettiest thing ever.
As for the LTR, it will be my next quad I'm sure. I got to ride Kaisers and the power band was so smooth. I'm certainly in love with EFI.