Both LOTR and TOM are top 10 games for most people, so they are both great games. Something to keep in mind, LOTR is new, you can still get one NIB. If you happen to find a really nice TOM you might want to give that a shot. They made a ton of LOTRs, they are easy to find. TOM, at least really nice ones are only going to get harder to find.
Whatever you choose, if you get a good price, you'll get your money back. I don't see the value of either going down any time soon.
In terms of my own personal view, no brainer, LOTR.