Learning curve can be arduous with learning linearization and/or paying them $100 for each new paper you want to have profiled and wait for the results to come back which I think is an absurdity too! They should offer their software to do it for pennies, or even free, since the price of the ink is very high and many have the hardware to read the values anyway. Sending off $100 each time you want to try something that may not be working right or some new paper and waiting is ridiculous, imho. Having a customer in your shop wanting it today or tomorrow isn't going to work if you have to wait 2-3 weeks for a profile to come back.
I'm going to disagree. There certainly is no need to learn linearization. Nor is there a need to pay for custom curves unless you have an unusual paper or your printer has drifted significantly from original spec. Canned curves exist for most mainstream papers.
There definitely is an upfront cost to getting started with Piezography. You have to buy the refillable carts. And you have to buy a set of the Piezo inks. The Piezo ink cost is actually about half what it is with Epson (around .37/ml for the 220ml bottles from Cone versus .67/ml for the OEM Epson carts from Atlex).
And there is, as you might expect when moving to a 3rd-party black-only ink set, something of a learning curve. I don't know that i would call it arduous so much as irritating. I've complained before that Cone has too much necessary information spread all over his web site. A prospective user should plan on spending an afternoon perusing the forums there. That said, 90% of what you need to know is laid out very clearly in one place - in the Piezography Manual Cone provides on his web site. It's an easy hour read.
Is Piezography worth it? Last fall I was where you are at now. I printed my work on a 3880. Mostly B&W on Canson's
Baryta Photographique. I liked Epson's ABW mode very much (I still like it). None of the galleries or shows where I exhibited looked at me askance.
Today, I wouldn't dream of going back to a K3 solution. I love the fidelity and nuance in having seven blacks. But the key word is 'nuance.' You need not worry that your OEM prints will suffer mightily next to someone's Piezo prints (or silver gelatin, or whatever other process). At the end of the day, a great image is still much more about the image than anything else.