In reply to philipivan:
I think it depends on how many hours a week you might ride, motivation, will you watch screen at same time, if virtual journeys or events appeal.
You've steered yourself away from that route already but I wouldn't use a good summer road bike for indoor training.
I think you'll soon get tired of any system where you have to turn a physical dial to adjust workload. A used indoor trainer and battered used bike gives you far more flexibility.
The next challenge is where to put it, you only realise how much the breeze you create cycling outdoors is cooling you when you start cycling stationary indoors. Cool garages etc.. are far better than spare rooms indoors, unless you turn the heating off.