This summer there was a big shake-up of print on demand. The prices went up steeply for two reasons. The actual paper jumped in price 8% and the print process used by DriveThru and their print partner Lightning Source had a major wobble.
The end result is that premium quality books have shot up in price, but the quality is certainly no better, some are saying it is worse.
This summer I have spent less time writing rulebooks and more time either writing GM advice books or playing around with cards and GM screens. Longer form books lend themselves more to simple design and black text on white with hardly any art. The value is in the words, there is no need to inspire the imagination, as there is with a game or rulebook.
This prompted me to try printing using the B&W standard. I have to say, even comparing the two formats (premium color vs B&W) side by side, the B&W stands up tolerably well.
The print cost of my first B&W book this summer is $3.03, The same book set up as premium color would have cost $10.96, and that is just the manufacturing cost. I am happy to sell that book as a physical book for $7.99, and I will still make money on each sale. Bumping it up to $15.99 just to make about the same return seems rather steep.
If you are looking to publish something as print on demand, I would seriously suggest that you get a B&W and Color proof and see which you want to offer, or offer both!