Airist Audio discrete R-2R DAC, at an unbelievable $350!!!!!

I have been trying to figure out what price point DAC I should get and I think I am going to order this one.  A bunch of people seem concerned that the ladder DAC design implementation is copied, but they have provided a side-by-side photo of several others and they are all so similar that I agree with their point that the real design is not the ladder layout which is very straightforward.

Would this dac provide a substantial audible improvement over my OL DAC; (using w/ Stax cans and Stax 313 solid state amp). My music source is iTunes files over Iphone 7; primarily live soundboards. Thx for your help. 

What " OL DAC" have you got make/model? some R2R old ones are very good still.

Cheers George

Thx George. JDS Labs current ol dac.

Hi mstrauss, sorry when you said ol dac I thought you meant an old R2R dac.
From what I found out the Ol Dac is not R2R multibit as it does 192 upsampling, so it’s most probably delta sigma.
To me R2R has it over delta sigma when converting redbook pcm. And for dsd what I found the Ol Dac can’t do it either.

Cheers George