Yep, sure did. Most of them were sold to Comet for use in their RTF planes. The deal between Fox & Comet went sour and there were many Fox engines sold after being returned by Comet, which had the Comet logo scrubbed off and the intake cut off at 45º, just to distinguish them.
While MECOA has purchased the rights to Fox engines, complete new .049 FIA engines and parts are available from Matt at
http://www.exmodelengines.comMatt acquired them I believe from Doug Martin who has been selling old-stock .049 engine parts for many years.
While I have one, I can't really comment on what their performance is like compared to the benchmark Cox .049s. Their tank mount has the same footprint as a Cox Babe Bee/Black Widow etc.