Anyone running a Diesel Geek Oil Cooler yet?

http://www.dieselgeek.com/oilcooler.htm
I'm looking for impressions from anyone who actually has it, as opposed
to theories on whether it'll work. It's basically just a larger than stock oil to coolant
heat exchanger.
I've been considering a regular oil cooler for a while, but my concern is about low
temp (wintertime) operation. Sandwich plates allow a small amount of oil to flow through the cooler
even when they're "closed", so in the winter you still can get some noticable cooling of the oil,
to the point that it may never come up to proper operating temps. The problem was reported
by someone using the Neuspeed oil cooler some time ago. He had a normal sandwich plate
and ended up having to put cardboard over the oil cooler to get the oil temps
up to a reasonable level.
Anyway, this diesel geek unit looks like it might help. It can't possibly be as effective as an
external cooler, but our cars seem to be pretty good at holding the water
temp at 190F, but the oil temps always skyrocket, so an improved oil/water heat
exchanger should bring the oils temps down noticably. I know that on the track it's
unlikely to help much as I've seen my water temps start to go up after only 2 or 3 hot laps,
and this will only make that happen sooner but for normal sport driving it should work fine.
If anyone has one, I'd like to hear your impressions.
ian