[MattyC]

In my opinion, PSA cards cost me more as a collector because their Registry has such a rabid user base; heated PSA Registry competition creates higher prices for those slabs and also creates greater demand for graded PSA commons, hence more of their slabs being sold.

The upshot of all this is that PSA cards wind up costing collectors more because this PSA Registry demand is priced into those slabs, to some extent.

As a buyer, where possible, I try not to pay a premium for a game I personally do not play. That said, when I am seeking a card I will find the card I want, and whatever of those major TPGs has slabbed it, is fine with me.

Of course, I can see sellers desiring PSA for these very same reasons, just being on the opposite side of the table. Though if any sea changes were to take place in the TPG landscape, selling would turn to whoever is the market leader in X-many years.