Moving house / keeping cat in

[CantChoose]

We are looking to move and have found the (almost) perfect house.
It has a much bigger garden for CantCat but I'm a bit worried that it's a corner plot so two roads alongside. They're both 20mph limits but I'm still concerned. There's lots of land to the back, but it's quite a busy farm and the vehicles are kept right next to the house.
I've been looking online at fence ends and rollers etc. Do you think it's feasible / cruel to try and keep him in the back garden only? Anyone have any experience trying to keep a cat contained?

At the moment we live on a very busy, fast road but it's a middle house in a long terrace and he only goes out the back door so its quite hard for him to access the road.

It's not at all cruel. It's sensible. I know people who've used ProtectaPuss type systems very successfully (and one even managed to trap a burglar too :) ).

Thanks, catneuterer
I spent the morning retrieving him from bullying another cat in the gardens so the idea of keeping him isolated is increasingly appealing great news about the burglar too!
We are having a second viewing at the weekend so will have a closer look at the garden boundaries with DH and see if we think it is do-able.

Not cruel at all, in fact very responsible. Take a look at cat fencing, it's expensive but worth it.