Sometimes things are simple. Sometimes people try to complicate simple things.
And sometimes people are too ignorant to consider all the factors that would help them make the best choice.
2 choices, one answer. No other reasoning needed.
With out factoring in all the relavant factors you get a pretty worthless answer. I might tell you that I would obviously get the .243 and that the 6.5 is not even worth considering. That would be because I greatly prefer varmint hunting to big game and when I do hunt deer I use a muzzle loader (plus I already have other good deer guns). Does that answer mean much to you if your end goals is to shoot white tails and you have a .223, 22 Hornet, a 22-250, 204 ruger etc already in your safe.
But if you still don't undertand my question , then look at it as this is the only gun you can have with you right now. No other calibers anywhere in the stable.
As was pointed out above this still doesn't provide the most important info, what will you be using it for.
The problem of asking which would you rather have outside of any external influences is that the answer depends entirely on external influences. Certain calibers and guns are better for certain uses.
If I already had a good deer rifle and wanted to shoot varmints .243 If I already had a 22-250 and wanted to shoot deer I would not have to think twice about getting the swede.
If I had no guns and was looking for a dual purpose gun it would depend on other factors. How much do I do of each thing, what type of deer are we talking about, a big mule deer is very different from a small white tail.
I'm not sure why someone asking for more info to give a better answer was deemed so objectionable. In fact one of the things that repeatedly amuses me is that people will ask for opinions on a gun and people will start spouting off with out having an information about what the intended use is. Given what you want people to base their response on you might as well flip a coin. People will at best tell you what suits them not you, and unless they elaborate as to why even that info is of very limited value.