need opinion from anyone who switched from 1DS3 to 1DX

Okay, everybody talks about how fast 1DX AF is. I now it has more AF points than 1Ds3, however my Ds3 autofocuses very fast and snappy with lenses like 24-70L or 70-200L, so I was wondering how much faster 1DX really is since my 1 is lightning fast when AF-ing and is it really worth upgrade considering the price of 1DX and the price I paid for 1Ds3! I mean if they had some marketing offer like bring your Ds3 and get 1Dx for 50% of full price...okay, but like this....nope!

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