How's the quality of option parts from Atomic, and GPM for m18??

i know the best quality option parts are xray, but they are very expensive. i want to know which brand name has better quality and higher preicion, atomic and GPM, or any other brand name? i live in NY, and i heard some people said there are different quailty for HK local market and oversea market, is it true? so which market has higher quality? oversea market or HK local market? thanks

if anyone have any option parts from any brand, please leave revirw for the parts. the quality, precision, characteristic, and recommendation?

GPM oversea product is better then HK local product.that's what i heard from other people from local...I have been used GPM product(bought from USA) now on my M18...it's good,
You can choose the upgrade option with GPM, ATOMIC, Jwerks, X-ray....

Jwerks product seldom saw in the market now....I heard that is Japan product(not sure)

I've not tried many option parts but I recommend you NOT to use the suspension arms from Atomic.  I've tried their 6 deg caster front arm and it broke without any collision after 2 - 3 runs.  Just broke naturally.  On the other hand, their springs and adjustable suspension are OK.