I have both the f4 and f2.8 with IS. The driving impetus to get the f2.8 version was for the extra stop to freeze action when used indoors and at dusk and dawn. For the focal length range you are going to find that f4 with 3 or 4 stops worth of IS improves handholdability provided that the subject is not moving fast enough to cause motion blurring. Unless your venues are better lit than what I am familiar with here a 200mm lens without IS is not that useful for a handheld shot unless your camera body has clean output at higher ISO to allow obtaining a high enough shutter speed to avoid camera shake. On a tripod IS not that important anymore.