<VV> question about valve guide liners

[John McMahon]

Hi,

I have no urgent need for these, but I'd like to get the group's opinion on 
valve guide liners.  Are they pure gold, or total crap?  Something in 
between?  Is proper installation the key?  Is there any hard data to support 
the use of them (or to discourage their use)?  Can they be used with bronze 
guides, or only iron?

Thanks!

John McMahon
1965 Monza coupe