How's the Televue 2.5x barlow?

The forum from earlier this week lauds the 2.5x Powermate (as does everyone who ever talks about it). For a less expensive option, how does the older Televue 2.5x barlow compare? Is its performance similar to that of the new 2x and 3x Televue barlows? I'd appreciate feedback from anyone who has used it.

I had one many years ago and I thought that it worked fine. I later had a TV 2.0x barlow and I don't recall there being any quality difference between them.