I flew 185s on floats, amphibious floats, wheels and skis (straight and retractable) for a number of years in Alaska. I loved those airplanes, and still do. These were all "working airplanes" meaning a variety of tasks, including hauling full loads of people and gear, radio telemetry flights which typically had just two up and lots of gas, etc, etc.
Then the crew took a vote (I had a boss who believed in "equity", whatever that is) and they chose a 206 to replace the 185s we had been using. Once that decision was made, I insisted that since we were acquiring a 206, and that plane was going on floats, it HAD to have an IO-550 engine. Wipaire rebuilt a U-206F for us, equipping it with an IO-550, a co-pilot door, and Wip 4000 straight floats.
We operated from the Fairbanks International Float Pond, which is a narrow ditch, a bit over 5400 feet long, and lined along the bank with seaplanes, parked. So, very easy to judge takeoff distances. Having operated a couple different 185s on both PeeKay and EDO floats out of that pond for a number of years, I had a really good idea where one of those planes would launch from that pond. This was not based on distances, but rather by "Launched right next to "so and so's" Cub, etc. Easy to compare distances.
At first, I really disliked that 206. As Pete mentioned, controls are heavy ("truck-like" to some), and those big floats kind of had me buffaloed for a bit. Then, one day, I figured out the magic to launching those big Wip 4000s, and, with a bit more practice, I was regularly launching within 100 feet or so of where the 185s came un-assed at gross weight.
But, here's the thing: Those 185s all went out at 3350 max all up weight. That IO-550 206 on Wip 4000s left at 3800 pounds all up! So, 450 pounds heavier, and launching within about 100 feet of where the 185 did? I'll take that every day!
Heavy controls: Yes, if you're driving around looking at stuff on the ground, while low level, heavier controls are kind of a pain. That said, I did a lot of radio telemetry locations with that 206. Makes for stronger left arm.
BUT, this is a "going somewhere airplane", not a "poking around in the weeds plane", and enroute, set it, trim it and forget it, even without an autopilot. The 206 was meant to go somewhere. We were prohibited from single engine IFR by policy. That plane was a magnificent IFR platform, however. Don't ask how I found that out.
On wheels, the 206 is a TRUCK! I was regularly moving things like 16 foot inflatble boats with outboard motors....and of course, these folks quickly discovered 4 stroke outboards. Try yarding one of those pigs out of the back of a 185 sometime...... When parked, the 206 floor is mostly level, the 185 floor has a serious slope to it. I hope I never again have to haul heavy stuff out of the back of a 185.
206, as someone noted, is a true six seat plane. The far back seats aren't real comfy, but the forward four are, and the two back seats are fine for smaller adults or kids.
Stewart argues for the co-pilot door. It's available as a mod from Wipaire. And expensive. If I owned a 206, I'd spend that money on gas. Look, almost every low wing Piper, every Beech Bonanza, and many, many other types of aircraft only have one pilot side main entry door. I'm okay with that. On floats, it is REALLY nice to have at least one additional egress door up front, though. But, at what price?
Stewart also noted the safety mod to the cargo door. I've never used one, so don't have experience with it. Now required in Canada, I believe, at least on floats. Not a bad idea, BUT, if you're flying a 206, you REALLY need to take your responsibility as PIC to heart and perform a SERIOUS passenger safety briefing, with emphasis on how that cargo door functions. On floats, I simply never really considered it a viable egress route in the water, but that's me. Problem is, flaps down blocks the front half of the door from fulling opening, which means the latch prevents the aft half from opening.....without some machinations.
BUt, to me, that's all trainable information, especially if you're flying the same folks all the time.
Skis: A fellow named Joe Matty operated a U-206 for many years out of Fairbanks, on Fli-Lite hydraulic retractable skis. Joe was both a trapper and a fur buyer. I've seen that plane parked in places I'd have to give serious thought to landing in a 185......out in the bush at trapper's cabins. I've only flown a 206 on Fluidyne retractable wheel skis personally. Those skis' performance sucks in deep snow on ANY airplane, in my experience. Fortunately, I didn't fly that plane much. But, on the RIGHT skis....the 206 does really well. Consider that in deep snow, FLOATATION is your friend. And, the 206 has THREE great big skis, compared to the 185s two big skis and one itty bitty one......think about that.
Wheels: The 206 is just plain a magnificent load hauler, and it's fast. Lots of cabin space, great useful load, good speed, and pretty much as bullet proof as any Cessna.
TU-206 vs U-206: Can't help much there. The key there is if you REALLY NEED to operate heavy at high density altitudes. That's where a turbo-anything shines. I've never worked TU-206, but I think if not on floats, engine reliability can be good, AS LONG AS the pilot learns to operate that engine.
But, then the pilot SHOULD learn to operate ANY engine they're flying.....just saying.
The bigger difference, in my opinion, is the difference between the "legacy 206s", and the "post shutdown of production" 206s. What I'm calling the "legacy" planes are the 206s up through the U-206G models. The "post shutdown" airplanes are all U-206H models. The most notable difference is that the early 206s all had big Continental engines: The P-206 used an I)-520 rated at 285, the rest of the legacy planes all came with Continental IO-520s, rated at 300 hp, except for the TU-206s, which had TSIO-520s, rated (if I recall) at 310 hp.
On the other hand, ALL the -206H airplanes came with big Lycoming engines. The U-206H with IO 540s rated at 300 and TU-206 with TIO-540 engines....not sure rated hp.....but 300ish.
So, if you really like Lycoming engines, the H models may be the hot ticket. I'm pretty sure that a much higher percentage of H model production has been TU equipped than was true of the earlier 206s.
The other characteristic of the U and TU-206 is that they are HEAVY. Lycoming engines are heavy, and Cessna seemed determined to pimp these planes out to attract lawyers and doctors, as opposed to bush operators. Leather interiors, etc. Ultimately, this resulted in Cessna increasing the Gross weight, to try to recover some of the lost useful load.
I really, really like 206s. If I were going to work an airplane of about that size out in the pucker brush again, on floats, wheels or skis, I'd go for the 206 EVERY time. No hesitation or qualifier.
MTV