"Panoptic Interface" with non-TeleVue Barlows?

Can the inexpensive TeleVue "Big Barlow-Panoptic Interface" be used with other manufacturers 2" barlows to effectively give them Powermate like qualities, such as stable eye relief and reduced vignetting? This thing is going for $65 new at present. My thought is that adding one to any economical 2" barlow might "potentially" result in the equivelent of the "poor mans Powermate". I'm surprised that I've never heard of anyone attempting this.

Did the 2" 2X GSO barlow vignette noticably more with the Panoptic Interface inserted than the Big Barlow did with same? Did either vignette more with the interface installed than was noticed without it installed? Was sharpness noticably affected on or off axis for the GSO and interface combination?

If the negative FL's of the two barlows are similar overall, I couldn't imagine the outcome being much different.

Bob, how many millimeters into a 2" barlow does the Panoptic barlow Interface insert? I'm wondering if it would fit into the 2" Antares 1.6X barlow without hitting the top most element (since the Antares is a 2" 'shorty' barlow). The pictures seem to show it as being quite short in this regard, but a measurement would be great.

Here's a link to TeleVue's old "Ask Al" column, where in the year 2000 I 'asked Al' if there would ever be a 2" 2X Powermate. His reply to me is the 38'th item down from the first one on this link. Here he tells us that the Big Barlow with the Panoptic Barlow Interface installed "is" a 2" 2X Powermate. He did however eventually come around and make a real 2" 2X Powermate. :-)

http://www.televue.com/ask_al/Ask_Al_Frame.asp?AATopic=barlows