Burgess/Back planetary eyepieces??

Stumbled upon the part of the Burgess Optical web site where the new 60 degree, 20mm eye relief, Pentax-like eyecup, planetary eyepieces were described. Only $99.

Designed by Thomas Back with a link to a yahoo group posting by him about the design. They sound incredible.

Are these out yet? Any judgments? How do they compare to the Radians, the most similar eyepiece out there vis-a-vis the specs? How are they on DSOs?

The first version of the 6mm, as described in some detail on the web site, is available, and my understanding is that the 4mm should be in transit from the manufacturer to Burgess if things have gone according to what Bill told me a couple of weeks ago over the phone. There are a few 4mm prototypes around, one of which is in the possession of Tom Trusock, who has tried it but is probably just waiting for some decent planetary observing conditions to give it a critical test drive. I don't remember what Bill said about the 9mm availability, but my vague impression is that the announced 3 focal lengths would all be available in a matter of weeks (the 6mm now, the 4mm next, and then the 9mm) with the aside that the 6mm as it is being sold today will not be the final version. Burgess has plans for more focal lengths, but he has to fund the production of additional focal lengths with proceeds from the sale of the early focal lengths. I think maybe a 2.5mm is next in the pipeline, or maybe a 5mm. It sounds a little bit flexible. If there's a particular focal length you would like to see, you should probably let him know when you order one of the announced focal lengths.
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Mike

Larry, I've got a 6mm prototype arriving today (maybe). I'll post some first impressions if the weather cooperates.