What to decide?!

[YKSE]

How about the difference between 200/1200 and 200/1000 which one is better?

Both 200mm aperture, they should perform quite the same when using the same magnifications.

The main differences between two are the followings:

1. The first one is a f6 (1200/200=6), the second one is f5, so the first one is easier on eyepieces, you can get away with relatively cheaper eyepieces, and still get quite sharp star closer to the edge, while with the f5, you might need to spend a bit (or quite a bit) more on eyeieces, if you feel the outer field is too nasty to see.

2.The first one is 200mm long, some 0.5kg heavier than the second one (about 9kg), therefore bulkier. The second one is already on the limited of EQ5 as I see it, the slightly heavier, especially long OTA of the first one may very well too much for EQ5.

I like EQ mount personally,for its the simple way of tracking, but I've set a SCT C8 on EQ3-2 as my portable setup, I can lift the whole setup in or out in seconds when observing at home, and travel to darksite with only half the booth filled.