never heard of it, looked at "Download", saw a big apple and a big window, no penguin. fail. also closed source AFAICT. thunderbird would be an incredible email app if only it had better maintenance.
Well it does the job already, working just fine for the 31-years-old IMAP protocol, the 33-years-old POP protocol, the 18-years-old RSS protocol, etc.. I might like an "incredible" email app but all I really need is a "sufficiently solid" one.. =)