I use Incredimail on occasions, but the only problem is, there's no way to export mail from IM, should you choose to switch to a 'conventional' mail client. I also don't like the fact that in the free version, it puts a tagline on all your outgoing mail. It's not a criticism, just a personal preference. Nothing is for nothing, and they have to advertise, in the hope of getting people to cough up for the Premium version.