I found this post on another forum by someone that owns both. Thought some would be interested.
> How do they compare as pad devices? Will the upper f100's like the
> F165 work as effectively, or is it apples and oranges?
I have both the Atelier Robin F165 & also a GB4000/amp - Both are
highly effective - The F165 has considerably more power - The GB4000
can run 6 channels at once so their preprogramming is very useful
although plenty of good F165 software is downloadable from Dr Loyd's
Overall, I prefer the F165 - $800 compared to $2200 - Very compact &
good while travelling plus the F165 drives plasma devices without
modification - Both units are recommendable - Probably the best two
contact pad devices on the market.