I use a turbo for recovery from injuries that prevent “real” riding (I.e in a sling), specific training sessions (intervals and the like) and also for rainy day riding. I also find, if I have a day to myself and fancy watching an old movie or documentary then doing so from the turbo is quite satisfying (Rocky, Battle cry, 3 hours of tour de france history).
Turbos are great in as much as you can put a normal bike in there and get normal position (if you raise the front wheel a bit). The resistance does feel a little riding through custard or as if someone is gripping the tyre a little which isn’t natural but you get used to it. They also eat back tyres and I seem to have buckled a few front wheels on the turbo too.
I’ve never tried rollers but would be tempted as it seems a bit more natural and you are actually riding the bike rather than just turning the pedals.
Exercise bikes don’t appeal to me. They never feel right, from the cockpit to the bottom bracket. Maybe its just a cheap model thing, but even the ones in the gym don’t feel like bikes!