It may not be worthwhile running your audio device at that high a sample rate. Lots of inexpensive audio devices have significant IMD at the higher rates. Try this test:
https://xiph.org/~xiphmont/demo/neil-young.html#toc_1ch
If you don't hear the ugliness in the samples when you're testing at higher sample rates (be sure to set your audio device to the appropriate sample device in Reaper so it doesn't resample the files), you can use whatever higher sample rate you want and know it's not going to be ironically sabotaging your efforts for higher fidelity.
Otherwise, you might as well stick to a sample rate your audio system can handle properly.