You can now, as well as picking different rollers to do different things. They say that you won't get as bored because you need to concentrate and that you replicate normal riding more closely because you need to keep your balance.
Back to turbos then, get a fluid or mag turbo not a fan. And don't worry about variable resistance or owt. You'll probably get on warm up and beast it, then climb off , no need for anything too fancy.