Filters and guiding stuff help please

[TareqPhoto]

Just got a budget although it is not bad but i have to squeeze it for few items only including one expensive item, so i have to make sure all items i buy are right choices.

 

1. Chroma Oiii 3nm over Astrodon because it is cheaper, agree or no?
2. Should i buy OAG according to the guiding cam or imaging camera? or it doesn't matter really?
3. Does anyone here used dark filter for dark frames? if so what is the impression?

 

I have to think about a filter wheel, but sounds i will pass it for now and try hard with what i have for miracle maybe, so if i will use ZWO filter wheel which has smaller mount adapter or window than QHY so not sure if OAG should be from ZWO as well or from QHY, my main camera is QHY163M.

I have to decide very soon, so within 2 days i will order it and hopefully i don't regret it,, i may try to go with guide scopes i have, but something telling me that with the Newt 8" the  OAG will do me better job and less issues once i set up it properly, for my Canon lenses or even future refr i can use whatever guide scope i have, but i keep thinking about my Newt to be used as soon as possible, for DSO at least, it will be fine over planetary imaging, but it must be combined with guiding anyway.

[TareqPhoto]

Please delete this thread/topic, no need to keep it now, thanks.