I hear you. While I'm not a big fan of add-on overdrives, I think I'd add a Gear Vendors to my TH400 before going with a 700r4 in my tow rig. I'm hesitant to run a 4L80e mostly because of that little 'e' and the expense and complication associated with that.
If Phoenix says it will work and warranties their work I'm not going to argue. But I'm also not likely to buy.
