Ducted fans for the tail, pros/cons?

[Rick]

Ive seen a few mini helicopters done up with a ducted fan taking the place of the tail rotor, and I find the design to be visually appealing, but I wonder if anyone's flown one and can comment on whether or not the idea works in small scales like Shogun 400 size.

One even had a vacuformed body to simulate a Coast Guard chopper.

Of course, now I can't find one on eBay to link to as an example.

Any thoughts, or even better, experience with this sort of design?

[hoverdown3k]

I have seen micro like the humminbird with a EDF for the tail, it looks cool, but I am not sure how well it works

EDF are not as efficient as a prop. Also the extra weight from the duct itself.

The spool up times are slower for a EDF also.

I still would like to put one on my HB V3, but have not seen one on a 400 sized chopper.