LTAs and BTAs are both considered "more hardy" among anemones. That said, a "hardy" anemone is almost a contradiction in terms anyway...
Anemones will move. You cannot prevent this. If they are happy they tend to stay in one spot, but then they can always split and send a clone on a hike through your tank. Anemones, while often kept in reef tanks, are not reef safe. Be warned. Sooner or later you will have an anemone migrate over one of your prized coral specimens.
I vote BTA if you are going to get one. BTAs are from the Pacific and are a more natural and more readily accepted host for Clowns while being less potent with their stings than some of the other anemones.