Is the Canon TL-H43 1.7x worth the money?

What kind of image quality can I expect?

I want to use the Canon TL-H43 1.7x for telephoto shoots of Birds. But, I want high quality shots.

Dave

there is a thread talking about it...

http://www.dvinfo.net/conf/showthread.php?t=94394

and here is some sample footage

http://file.meyersproduction.com/hv20/tlh43/

Is it worth the money?

I don't know how much this helps but for me personally I think the lens is worth the money if you're shooting wildlife. Otherwise no. Everything else said about the lens on DVI has been spot on. Lens quality is good but the wideangle lens portion is worse than worthless because the lens is in the picture for half the zoom. I think you'd be better off stowing it for any shot that might require pulling back. I just got back from shooting a doc on beer and monks in Belgium and lugged the tele around on my bike for a week (it weighs as much as the camera), used it twice but never needed it. However, if I were planning a trip to Africa or even to yellowstone I would feel the lens range would be essential.

How does the 1.7 lens compare with using the Digital Zoom at the same focal length?

I own a HV 10, and the video quality is better using the HV 10 digital Zoom, than it is using the 2X convertor that I bought for it. However, the 2X was not a HD model. The HD model should be better.

Now I think I see why you're questioning the telephoto. Yes, to my eyes, the HD lens seems much, much better than the digital zoom. I'm guessing you got the telephoto lens for the HV10 at a very affordable price point. No worries with the HD telephoto. You won't be throwing away money. I wish I were a little more internet savy and could post the difference.
Anyway, If I were in Alaska and planning on shooting birds that did not require lots of zooming out, I would go ahead and bite the bullet on the telephoto--even if it's worthless for half the zoom--if I could scrape up a little dough.