my first question is can it be used on the mission exotic or mission dyson. 2nd ? is what is the best use for them i dont have any mega rich planets yet other then the mission ones and dont see me getting any in the near future. so do i hang on to them or put them on the mission planets. also my mission planets are set up for artifact production right now so really confused as in what to do.

Wait until you have a maxxed out planet then use them.

Yes you can put them on mission planets although personally I would wait until you get a Colossal17x plasma planet or higher and then use them so you can streamline research, like you said you have your mission planets set to arti which is the most useful resource so well done there, and there's not much point putting them on an arti planet unless your getting a lot of secondary research from it.

The Higher the Research Richness the better. 17x Research is the max on a VM 15x Gas after making it a Colossal Plasma. I say never use the cubes unless it's on it's maximum.

personally what i plan on doing with my cubes is getting a gas to 15x then 20x with resequencers then 26x with data cubes and then finally 28x with plasma transformation, but that is just my opinion everyone has there own some agree with mine some don't. Also i wouldn't put them on mission planets i would only use those planets for artifact production mainly with a little research or mining only as bonuses.

Waste of Resequencers, but it has a nice idea to it.

Bad idea, use resequencers ofr arti and thinking about it, putting them on mission planets could be a good idea as it can never be taken away from you.

Sell your resequencers and I bet you get some good research planets in trade. Lots more than the 5x boost you are talkin about.

Don't sell your resequencers they're one of the incredibly rare artefacts that go over the 15x cap, and if you for some reason decided too, then buy arti planets not research planets.