RexWireless has done a terrific job with the "matrix" applications. They have great tech support and have continually updated the software adding features. They are very receptive to user input and as you can see by thier comments to increase the text field for todoMatrix.
One suggestion for you, if you plan to use "inject into" with the email application you may be better off getting ideaMatrix. You may be disappointed with the limited text field in todoMatrix, IMHO it cuts off too much of the message. Better yet, get the silver package - both programs are worth the cost in my opinion.
Personally, I'd like to see todoMatrix have the ability to take information from an "inject into" email and then have the ability to automatically populate the search box so you can find the original message in the message application. I'm always trying to locate the original email. If not that, capture sender, date, time and subject (rather than all the header information) and as much of the message that will fit.