Buy and upgrade an ARC Ref 75 to 75SE OR buy a new/used 75SE?

I'm thinking of buying an ARC Ref 75 and sending it to the factory for the conversion to 75SE.  I hope this won't lead to a compromise in product quality.  Any advice would be welcome. 
Personally, I would just buy a used ARC Ref 75SE, as it would probably cost you less money, and most of the components would be newer.

Recently, I just bought a ARC Ref 5SE and sold my ARC Ref 5.
ARC quoted me $3500 to upgrade the Ref 5 to a Ref 5SE.
By doing it my way, I saved over $2,000.

And while the new SE pack of capacitors is older doing it this way, the other 80% of the parts of the 5SE I bought were a couple of years newer than the parts in the Ref 5.
You'll be fine; performance should be identical.  Paying more money for a new unit doesn't make much sense unless you're OCD.