It's better NOT to run these obviously. Which is why I wish I had gone with 10.5s in the rear to begin with. I most likely will be removing the spacers when I have the slicks on. Even with hardened 31 spline axles. I don't want to risk it.
BTW - most of the time, if you can get tires at the same time as the wheels, you'll save some $$$. I would hang on to the tires you have for front replacements. OR save the old setup just as it is for winter. But that's just me. It's all a matter of opinion.