Bear in mind that this is a REVERSE indirect, and it will cause a non condensing boiler to condense under the right conditions. Obviously not a problem with a condensing boiler ,but definitely needs to be taken into consideration for non condensing appliances.
And they do make an ASME model.
It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.