Resolume calls for the DXV codec. it runs very smooth on my machines(OSX). I use compositions up to 6000x1080px. sizes vary to 1.5gb. Best results are with rendering original to DXV, otherwise you will see a quality difference(artifacts).
Not every 'VJ' uses the same res clips for their shows. IN my case, my content is specific for each show I do. There is math involved. Depending on how you are presenting your content (projectors or LED panels).
You will get more pixels out of most projectors. If I am using a single projector with the res of 1080, I make my content 1080. For LED panels, the math is in the pixels per panel by the total mapp of panels combined.
You can tell the difference in a trueHD show compared to a show that is scaled up to size.
A good "VJ" has the ability to be the video technician and content provider!