M42 to EOS AF confirm adapter VS Normal M42 to EOS

[Emperorwendy]

Hi, as title above, i am quite confused by the different mount there are in market. Was planning to buy a manual focus lens which is M42 to play with my Canon 350D. But when i look for adapter in the Tago Tech site, they had this 2 different converter which seems to me, have the same use.
Any kind soul out there will enlighten me about the differences of this 2? What does AF confirmation means? How does it works? Does it directly affect picture quality?

There is a big price differences between the 2.

http://store.tagotech.com/product_info.php?products_id=50

http://store.tagotech.com/product_info.php?cPath=22&products_id=68

Thanks!

 

[teebs]

If you are buying a manual focus lens, you dun need the adaptor with AF confirmation at all.