Just anecdotal information but I've had the Canton unit on my 428 since new (iron block, aluminum heads) and have been happy with it to this point. No matter what the outside temp it has kept the
oil temp at 85C (on my gauge) during normal operations. In colder outside temps (35 to 40 degrees) it takes a while to get there but stabilizes at 85.
During track days or "spirited" driving I'll get up into the mid to upper 90's but it comes right back down after a few minutes of normal operation. Have seen about 105 during one very long slow local parade when the outside temps were in the upper 90's but that was almost an hour of stop and go at about 5MPH.
The unit has been on the car for 5 seasons or 34,000 miles to date.
DonC