Not worried tbh, No matter how you slice it, it is still way faster than my card. So what if its got a lower stock speed. If the cooler is worse, then whatever. Damage is done. /shrug
EDIT: Review from newegg - Runs extremely quiet, as i said in the title, overclocks like a dream (mine is at 1420MHz), it can actually do 4K at ultra settings if you turn AA off and are ok with like 45 fps, and is aesthetically very pleasing. Runs GTA V at 1080p at 60% fan which is extremely quiet and still getting up to only about 65 C
That review is what sealed the deal for me.