A new stride frequency (higher or lower than you are used to) will naturally feel awkward and less efficient—it IS, after all. While research has shown that increasing your stride frequency by 5-10% will have a negative impact on your running economy, presumably because you are running in a way you are not used to, they have also shown that you are decreasing the forces that have to be absorbed by your legs each step. While it has not yet been demonstrated directly, high stride frequencies are likely to reduce your risk of an overuse injury, all else being equal. Anecdotally, many coaches have also noted that their healthiest, most efficient runners tend to have light, quick strides, while their chronically injured runners tend to take long, loping strides.
In my own experience, it will probably take at least a few weeks to feel like you are running normally again. Ideally you'd ease your way from 160 (an exceptionally low stride frequency, by the way) up to 170-180 over time instead of all at once, but now that you've started doing 180, you might as well continue.
Also, this probably won't impact your performance at race-relevant speeds because almost everyone increases their stride frequency to 180 or more when actually running fast.