(This ended up a little longer than I had initially planned, so I apologize in advance...)
Ok, here's my dilemna. I'm looking at getting a 70-200. Price tag has got me stumped. I really can't do the F2.8 with IS so I'm looking at the 70-200 f2.8 (non IS) vs. 70-200 f4 IS, mainly due to cost managability. Currently I'm using a 60D with 18-135 f3.5-5.6 with a monopod for equestrian competitions, little league baseball from the side lines, kids soccer games, travel, family, pets, and what ever else I can point it at. I'm thinking 70-200 mainly for the horse shows, baseball, and soccer games. I'm thinking larger aperture for some lower light situations together with the need for faster shutter speeds (indoor horse shows). My dilemna lies in which 70-200. The IS's are pricey but fantastic IQ. Winter horse shows (brrrr here in the north east) are often indoors under weird lighting, combination of filtered natural light, tungsten, and fluorescent, with dark and light areas. Horses are cantering and jumping so a little more shutter speed works best. Outside shows often require a little more ability to reach out than I currently have. My 18-135 on AUTO ISO often wants ISO set on 3200 for a 1/200 or faster shutter speed with wide open aperture. I'm thinking a larger aperture would let me lower my ISO for better IQ, but will I be ok without IS? Ideally I'd love the 2.8 with IS. The f4 will let me shoot faster because of the IS, but smaller aperature. Am I really much better off than my 18-135? For baseball, the action might need to be a bit faster, but at least it's outdoors in the daytime. Do I go for the f2.8 non-IS or f4 with IS (or save my pennies and get a used 2.8 with IS). I'm sure there are opinions out there. SO BRING 'EM !!! 

