Refurbished / Re-tipped Cartridges - Are they worth Buying?

Have never had an issue and in some cases they are better. 

OP states:

"much of the original design attributes are gone" 

Results vary...  I have had 4 identical cartridges retipped by the same vendor. Three sounded great, one sounded so-so...

Why?   All carts were UPGRADED to a better cantilever and stylus-shape.  The three 'good' carts were produced distinctly better SQ, the fourth cart did not.  Why?  I look at it under a strong lens, and the stylus was attached with too much glue.

Give upgrades a try, and work with your vendor to ensure the process is acceptable.

+1 dinov 

@cey 

Appreciate the list of reliable vendors, will keep this info for future reference. 

@inagroove 

Agreed, results of rebuild may vary and glad to hear your experience were positive. 

Inagroove, you have some expertise that allows you to judge the proper amount of glue used to fasten a stylus to a cantilever? Did you also look at zenith angle, when you examined that cartridge under magnification? You might be right about the glue, but it also could be something else.

Jonathan Carr (Lyra) who is regarded here as a major guru, wrote on this forum that it is wise to replace like with like, when it comes to cantilever and stylus, if you want to preserve the SQ of a cartridge. Because the other structural and functional elements of the cartridge were chosen with the OEM cantilever and stylus in mind. Thus, an “upgrade” may not necessarily be in the up direction. 

I guess you are talking about MC carts, as replacement stylus in MM carts are a non-issue, IMHO. I had my SoundSmith Zephyr MIMC* rebuilt by SoundSmith after a mishap, and I have zero issues with that.

With antique carts, I would rather consider them display items. 

Re slightly used, Audible Elegance just posted a video on used carts and strongly advises against them. Particularly the degrading suspension is an issue, and not perfectly aligned, partially worn stylus can damage records.