This version of SwiftMailer component is built under cake conventions and has ability to add attachments, plugins and SMTP under TLS or SSL. Also if you are using utf-8 characters Outlook uses different encoding for subject, so there is a possibility to change encoding for both: subject and message.
In this version message is wrapped like in cake's email component etc. email element is wrapped in the email layout for a content type used. I must mention that SwiftMailer library is under GPL license.
Thanks to Matt Huggins who was first to make this component under SwiftMailer version 3.xx