I too, use the Edge Insight CTS for our Ford Powerstroke. It is quite pricey but it provides a wealth of information. Probably the best value for the dollar would be the Scangauge II, at around $150 it also provides a lot of information via the OBD II port.
If your Trans fluid runs over 175* you might want to consider changing the fluid at shorter intervals. I do mine every 30K miles.
Steve, Berne and Rascal
2012 Jayco 31.5 RLTS
2007 F250 Powerstroke