If you don't like riding in ugly wet weather then yes. A couple of things to consider, I find it really boring riding a trainer inside and I overheat easily. So get an electric fan and ride in front of that, or find a couple of young maidens with palm fronds, which helps on the boredom as well
Also take the knobby tire (or tyre if you prefer) off the back wheel and get a slick, the cheapest one you can find as trainers tend to wear them quickly.