thanks all
I'll probably just a 100-400 for a weekend and see how I get on with that, they seem to be ok pricewise used. Even though it'll be the Gen1 version with the push-pull zoom. Cant say I'm a fan of that
regarding the 7d2, I had a 7d and hated it. I could never achieve a sharp image. Focus was fast, but every single image came out slightly soft. no matter how much time I spent micro-adjusting.
I put the same lens (a 70-200 L) on a 1div and bang, great shots every time, wonderfully sharp and in focus. To add insult to injury, Canon blamed all the 7d users for focus issues with the body. I now see similar reports of people taking the 7d2 back because they cant get sharp focus either - there really must be a load of other stupid photographers out there like me who dont know how to use that camera.