I have been using Google email service for long time and have a good experience. I feel no limitations about this service. But, does it have limitation-free service? It seems it doesn’t. There is a limitation about sending email using Google email service.
In an effort to fight spam and prevent abuse, Google will temporarily disable your account if you send a message to more than 500 recipients or if you send a large number of undeliverable messages. If you use a POP or IMAP client (Microsoft Outlook or Apple Mail, e.g.), you may only send a message to 100 people at a time. Your account should be re-enabled within 24 hours. (source)
Okey, there is a limitation. But, I don’t think that I will hit that. Do you?