Removing sources of moisture is more important. I don't like shower domes, but extraction is critical - kitchen, bathroom, and laundry. Ventilation by opening windows is mildly effective.
Condensation is caused by warm moist air hitting a cold surface - the window. The reason a ventilation system helps reduce (not eliminate) condensation is because it blows cold, dry air into the house, so there's less moisture and the air's colder. A more effective way to almost eliminate condensation is double glazing. The cheap way is to get a firm to fit 3mm thick solid plastic inside your existing window frames, if they can be mounted. It's basically cheap double glazing, perhaps $5K for the whole house, whereas replacing every window with a PVC double glazed unit will cost you more like $30K. It works almost as well as "proper" double glazing, but is a little uglier.
Plastic ground mat made a big difference to the damp smell in my house, combined with under floor insulation.
I do have a cheap ventilation system, only because it was in the house when I bought it. I don't like taking air from the ceiling cavity as it's a bit smelly in my old house, so I'm going to bypass it and draw in fresh air soon. That will still dry the place out, but won't warm it from the roof cavity air. I value air quality over warmth, I'll just schedule it to come on say 11-3pm, when it's warmer outside anyway. Because we have double glazing in most of the house we don't need it on all the time, it makes the place cold, blowing cold air in constantly.
Check out Cleanaire for a good value heat recover ventilation system. That's who I'll use when I eventually fit one.
This and much more on the older threads. Google will find them for you.