Very little is actually "good" out of the box, depends on your budget though. A TM is usually fine as it comes, a lot of others are in need of more power/RoF/trigger response from the get go.
Most stuff these days seems pretty good, out of the box anyway, even the 'cheaper brands' Double Bell and Golden Eagle have made some top quality aeg's. I generally snuff at anything that takes their own 'proprietary' parts/mags, like G&G. Cyma 'platinum' aeg's are very nice.