The rule of thumb is this...
If you are using a 200mm lense, in order to get sharp results (not because of the lense specifically) you must be able to shoot at F5.6 and 1/200th or faster of course. At 300mm, it's F5.6 at 1/300th. With my old lense, I'd be using KR64 and sometimes KM25 at 250-300mm at F5.6 at 1/60th. Sure, I'd lose a few blurry shots, but the sharp ones were awesome.
Now with a faster lense, I shoot KR64 at F8/11 at 1/500th-600th rather easily, but provided you shoot faster than whatever 1/xth zoom that you have, your shots SHOULD be sharp.
What other people think of you is none of your business!