Obviously comes down to personal opinion - I vote SM. I had a HUO LOTR as well, and sold it pretty quickly, I liked it but became bored pretty quickly. Can't put my finger on why, it obviously had a ton to do but after destroying the ring many times, and getting to There and Back Again a couple times, I felt like I'd seen all I was going to. Valinor was never going to happen for me, so I moved on after only a couple weeks.
I haven't owned a SM, but have played hundreds of times - feels better to me and is just more fun. IMO