I just went through this when deciding to finally work through The Little/Seasoned/Reasoned Schemer books. After spending way too much time stressing the implem

I just went through this when deciding to finally work through The Little/Seasoned/Reasoned Schemer books. After spending way too much time stressing the implementation I settled on (Petite) Chez Scheme. It was super easy to install, has great docs/guide, and works quite fast. My advice would be to just pick one and don't look back. I spent way too much time on it that should have been spent learning.