either will work fine. the non apv sleds aren't too picky when it comes to oil. i've used cat, amsoil, klotz, castrol or whatever might be available at the local auto store.
never had any problems, but some smoke/smell slightly less than others. just make sure its got the recommended certifications and you'll be fine. TCW-3 is all you need for non apv engines. JASO-FC and ISO EGD rated oils are recommended for newer engines and will work well in your sled but cost more.
a lot of amsoil fanatics on this site so i'm sure you'll get a lot of testimonials. between just cat and amsoil i would run whatever you can get cheaper.
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