Groandas

I am eyeing at either Beresford Caiman and Maverick D1 DAC + Headphone amp. I intend to connect this directly to my Mac Pro via USB. I will this up to Grado RS1i. Can anyone using either one of the following give his/her feedback. Thank You so much.

I made some extensive search on Grado RA1 and to my surprise, the parts used in RA1 are dirt cheap. I read an old post from this forum that there is a guy (not to mention name) used to sell the parts for a small fee. Appreciate if anyone in this forum could guide me through in getting the parts for RA1 clone. Thank You.