The updated eShop version is the definitive, more reliable experience. The NSP update is a gamble that usually loses.
Here is a helpful review and breakdown regarding the "better" option for this game.
The keyword phrase ends with —and that is the most important part. Version 1.2.4 (and subsequent minor patches) transformed Beach Buggy Racing on Switch from a "buyer beware" title into a genuinely great handheld racer.