It's good but if you are looking for single player then stick to GT3, in fact I'd say only buy GT sport if you have VR and it's on sale, I've had a ton of fun racing online in sport mode (ranked), doing the driver school and racing AI in VR tour but it's definitely not a game for single player racing gamers. If you have a wheel and want a good racer grab Project CARS (Not the second one, the first) or if you don't have a wheel stick to GT3 because you aren't going to get better on the PS4.
How can’t you recommend pCARS2 for offline content? It’s buggy, unfinished and has a much worse single player campaign than GT Sport.
It’s also much worse to play without a wheel.