I hunted for nearly 20yrs with NOTHING on my scopes. If it rained or snowed they got wet & a shirt tail dried em off. I grew up in the hunting fishnet biz & sold a blue million of the various covers but the only thing I used was the rubber bikini covers & I had a few Nikon's & they came with hard plastic caps. But those were removed while hunting. Then in 1999 I bought a Swarovski that came with customized Butler Creek Flip ups so I tried them. I haven't been without them since! I have 15 big game rifles & EVERY ONE of them have flipups on them. In fact if I have a choice, I prefer the clear/see thru "Blizzard" flip ups from BC. Those sudden "oh chit" moments are quicker without having to think about flickin the covers up, ESPECIALLY on my guns I use in the thick stuff! Touching/cleaning lenses is what ruins coatings & scratches them. With the flip ups I typically only have to "clean" them by opening the covers & blowing the light dust/particles off!