Yea those look very nice, you have a lot of skill, I can tell by the way your models look. I personally don't prefer 'photorealistic' models or textures, I thinks low poly & or 'cartoony' is a very fun and easy style for anyone to model in. Most of my models are made on the premise "It's not 1:1, it just has to have the look and feel like the prototype".
I don't think I have ever modeled a full brake system on a locomotive or car before, same for rivets. I just don't see a practical use in more meshes that just making renders and game performance less...
If I have to model everything to a 'T' I would never get anything done at all, or 1 model per many months...