Honestly there are enough good billet upper/lower manufactures out there that I would stay away from HERA.
I've seen issues with parts fitting, finish coming off (Cera-coat not properly cured or contaminated) poor quality machining... And they are a PITA company to deal with. I used to work at a company that used to carry them, and they (as well as Gravel) stopped carrying them for a reason.
It sucks because they used to be absolutely top notch stuff - and they made some really cool stuff, but they are a victim of their own success. Sacrificing quality to pump stuff out quicker, and not having enough quality control.