I've installed quite a few Broan htr/vent/fans and never had a problem with one out of the box. This has not been the case with other models.They have proven to be reliable and virtually maintenance free. When maintenance is required, parts are easily replaced.
I have an older home with old school Nutone exhausters. They are made from what appears to be an ineffective squirrel cage design. I wouldn't recommend them. Mine spin up fine, but don't really suck any air out worth a ****. The more modern ones may be a better product though.