Looking for thoughts on the STOL kit for the single turbo otter. Pro's/Con's?

Can't think of a downside on floats. On a wheelplane having a wing that is still providing lift with the plane in a 3-point landing attitude could be a problem when dealing with either a very short or rough strip or strong crosswinds. Sometimes you get in more trouble if the dam thing won't stop flying.
My 2 cents from observation but no actual DHC-3 experience!

I'm assuming your talking about the leading edge? Most pilots I've talked to don't really notice much difference. Not near as effective as it is on the Beaver.

I fly both. I much prefer the STOL kit. The take off and landing speed a little slower, want to hang a little before touch down. Depends a little on the engine. I like the Garrett only for the extra power, and love the fuel burn rate, much better than the PT6.

With the Barron leading edge, the turbo Otter fly like a normal airplane,
none of this nose down climb crap. However, it can and will fly slower than the ailerons and the tail feather can
control...several times resulting in planes flopped upside down near the ground in turbulent air.
Fly faster, then you float in ground effect and have to pop in the reverse to kill the lift.

If given the choice, the regular turbo Otter have all the lift you need for normal short field
or small lake operations.

I don't consider it to be worth the money. It makes the plane a little bit more idiot-proof, I suppose. An Otter equipped with the Baron leading edge can fly slower, and the stall behaviour becomes kind of atypical, in that there isn't any stall behaviour. It just sort of starts to fall, no buffet or wing drop. It flies so slowly you can plop it onto the runway in a three-point attitude in any amount of crosswind without worrying too much about using any "technique"...

I think your fuel burn would be higher with the baron leading edge, I seem to remember using higher power settings on the Baron-equipped Otters. Of course they all go 118 knots but I think it takes a bit more jam with the more lift-y wing.

I've flown lots of Otters with and without the Baron thingy, and I guess I like it better without, but not for any reason I can put my finger on. I found the plane's handling more "crisp" without it, I guess as "crisp" as the controls can be in the first place on a mushy old Otter.

I guess I just don't think all these "improvements" they keep trying to make to DeHavilland planes are worth much. Someone's always trying to come up with some kind of stupid-looking wingtip or other device that addresses a problem that didn't exist in the first place. The Otter is good without the gimmicky improvements. I suppose you can always justify a device that makes a plane able to go slower and "tames" stall behaviour, but I just don't think the Otter needs it. Plus, it's ugly.

The big improvement was to put TWO engines on the Otter...but it's like with the Beech 18 with garretts
the extra power make it go much faster but it turned two pleasant to fly airplanes into
damned pigs.

Beechcraft had a winner because they rebalanced the controls and made the King Air just as fun as the old beech 18...

You don't like how the Twin Otter flies?