Here is an example of the difference between the two sensors. The S50 is an older sensor so has slightly more noise, the S30 is an upgraded sensor, they are both still 2 mpx and same size and pixel density but the S30 is an upgraded sensor and it is noticeable in the noise in the fits image. You can overcome the noise with longer, i.e. more, exposures but it is nice to have a good sensor to begin with. SO when they say bigger and better, we will see what they do and when.
Here are two images, the S30 is on the left and the S50 on the right. they were not taken on the same night but they were taken about the same time with the same sky conditions. You can see first that the S50 has a bigger image size (they are both M31 the Andromeda Galaxy) the galaxy is bigger and the stars are bigger than in the S30 image, but you can also see there is more noise in the S50.
View attachment 12603