I think I have saved enough for another lens. Camera is a canon t2i. Came with 55-250 IS. I want a bit better lens. do I get the 70-300 zoom or opt for the 100-400 one. Going on vacation in about 6 weeks and want some good pictures. Can also use it for wildlife pictures at the farm.
Thanks

For wildlife, the longer the better. So, out of the two mentioned, the 100-400mm will probably be the better choice.

As long as you have the 55-250 lens, I wouldn't invest in the canon 70-300 lens. Now the canon 100-400L lens is a great lens. But you might want to check the weight on it. It can get heavy if you carry it much. If you are going to carry your camera equipment much, I good camera backpack will make life easier.

I have the 100-400mm Canon lens, and use it as my primary wildlife lens. It's a bit slower than I would like, but it is quick to focus, and the zoom makes it easy to find an animal and then zoom in on it for your shot. I haven't used the 70-300mm so I can't comment on that, but as has been mentioned, check the weight because it does get a bit heavy if you have to carry it around for very long. Good luck, and I'd like to see some of those vacation shots when you get back.