I found out why I changed. I use a DEA system for email so I need to be able to change the From: address to anything when creating an email and I need the mail client to be able to set the From: address from the To: field when replying to an email. Out of the box TB can only do this by requiring the user to manage multiple identities which is a bit tedious. Creating the first email for a contact means first creating an identity for them and over time you'd end up with a lot of identities in the list.
Thankfully there's now a TB add-on called 'Virtual ID' which looks like it can do exactly that. That's actually more elegant than the previous client which required me to write a slightly complicated script.
Biting the hand that feeds IT
