Should I stop or continue with more epochs?

I am training WGAN -GP to generate X-ray images. After 1240 epochs I came up with this image.

Should I stop here and make some hyperparameters tunings or should I continue with more epochs?

In addition to it, I would also like to know on average how many epochs are usually required to train a model which is expected to generate images.

Any help shall be highly appreciated.