However, third party lenses (ie. Sigma, Tamron, Tokina) often need
rechipping to work with the newer camera protocols
This is definitely
not correct.
There are several
older Sigma lenses that don't work on the newer
digital EOS cameras, but all the new DG lens work fine (at least,
until now). It seems that Sigma does not rechip those older lenses
anymore, so one must be careful.
There are no reported incompatibility issues regarding Tamron
lenses in any EOS camera. And older Tokinas seem to work fine also,
even in newer EOS cameras. I had one old Vivitar AF lens that also
worked without any problems.
I think that putting all third party brands in the same bag and
refering that 3rd party lenses
often need rechiping is abusive.
And your sentence also transmits the (wrong) idea that even buying
new lenses from a third party brand may be risky.
Best regards.
I sell cameras for a living. Third party lenses often need
rechipping after a number of years.
DG Sigmas work fine for now, but more than likely Canon will change
something in the future that will require some of them to be
rechipped. How far in the future is a matter of speculation, but I
have a Sigma that was bought in 2000 that worked on the D60 and the
original Digital Rebel but not the XT or the 20D. And yes, in my
work I've seen lenses from all third-party brands that have needed
rechipping, or at least that have caused errors on new bodies.
If you want to use third party lenses fine, there's some nice ones
available, you'll probably save some money too. But saying that
rechipping isn't an issue is "abusive" and "transmits the (wrong)
idea" that buying third party brands is without risk.
Warmest feelings.