True or False to which statement Rastis? You made 7 different points!
1. A 4 inch refractor will show more contrast
2. I personally think the images are sharper then a 8 inch DOB.
3. The DOB's images will definitely be brighter and you will be able to get more useful power from it purely because of its larger aperture.
4. If you are interested in planets the equatorially mounted refractor would be better because planets are seen better by using the maximum usable power that the conditions allow.
5. The higher the power the smaller the field of view and the quicker the image will drift from view.
6. much easier to mount a motor drive in the EQ refractor than a DOB
7. you can enjoy high power views without constantly needing to re-adjust the telescope.
Can you narrow the question down a bit to what you really want to know.