Based on what you said, you must be rich guy 
not all of us have that much money…
BTW this is just AMD marketing, I’m almost sure that all chips are almost the same product… but for for people who have enough money, AMD made chip with little more performance…
if you don’t plan to overclock your 550$ 1800X (3.6 GHz), then it will be slower than mine 360$ 1700 overclocked (3.7 GHz)… base clock of 1700 3,0 GHz is just trick to let ppl with money think about 1700X and 1800X… of course if i had more money, i would like to grab 1800X too, but i live in country where monthly salary is 400-700$ and even then i bought PC for 1900$… I’m just not rich enough to pay another 200$ for +0.3 GHz extra performance…
anyway mine overclocked 1700 running on 40C so its not possible to burn