
The 55-250 won't be for arena work, more for cross country/fox hunts and horses in the pasture.
I do plan on buying the nifty fifty but I wanted a cheap telephoto lens first to see if I'd rather stick with smaller zooms before I went ahead and started saving up for the 70-200mm F4L. I just don't know if I really have any use for longer focal lengths, which is why I want to go cheaper.
Thanks for the input guys, I appreciate it.
Then the 55-250 should fill the bill nicely. It is low cost, but it is very good optically, so it would be a good choice for what you want.