Apart from the leg length, you also have to consider the enjoyment of the trip.
You can go 180KTAS in a TR182 at FL200 but if you want to do shorter legs or see the scenery along the way you won’t even climb that high. It’s a very different experience than 120kt at FL80. Since the question was for VFR I think the latter is more likely the goal.
If you stay in a « normal » class of aircrafts (no offense Antonio), you get diminishing returns from 120kt up. 135kt can be a little pricier after that, but 150+ kt will generally cost you two extra cylinders and higher fuel burn.
In France there is also the (completely made-up) limit of breaking the 300km/h TGV speed (162kt) just to boast that it’s too slow for you (giving you an additional excuse to not go by train 
).
any stopping is a reduction in safety because of the descent, the climb, and wx changing.
Counter argument: if you don’t fly too often an extra stop provide extra descent/landing/etc practice, I am always grateful to custom stop helping me practice more :):)
To be honest I don’t see any legitimate reason not to go for the fastest one can afford and is qualified to fly. It just gives more option.
I think it’s really about cost as people pointed out. And cost can significantly/unreasonably increase with speed. And even a slow plane is already a privilege to be able to fly.
I flew a old c150 to travel around the American west Grand Canyon and national parks when I couldn’t afford more and loved it, and now old with more mean I am lucky to fly a cirrus in Europe and love it as well.
In general, it’s easier to make a fast plane fly slowly than the other way around. When it’s safe to do so, I fly as fast as the aircraft will go. The little travel john bags are really useful – I’ve used them several times even on shorter trips, due to bad planning, too much coffee, etc.
eurogaguest1980 wrote:
In general, it’s easier to make a fast plane fly slowly than the other way around.
I was going to say something similar. You can fly slow in a fast plane but you can’t really pull out that extra bit of speed on a slow one.
When I started looking for a plane to travel with in 2009 I looked first at a Cherokee 140. Cheap to operate and with a good range at 50 USG I did a few flights with it and almost fell asleep. That particular airplane flew 90-100 kts using 6-8 GPH doing it. Coming from flying Senecas before, I started to do some calcs and did not really get warm with it.
When I was about to put it in pre-buy, one guy at the maintenance said, why don’t you talk to xxx he has that Mooney for sale, probably even cheaper. I was very intrigued as I had never thought I’d be able to afford a Mooney and went to fly with the guy, who is an old friend of mine. This plane does 150 kts on a good day but mostly 140-145. If you fly economically, 135 kts high up with 8 GPH. I have not looked back.
I later on did some recalculations. The Mooney is much more efficient on almost any trip, simply because it is at least 30 kts faster at the same fuel flow. Also the fact that it is faster, it has a bigger range with the same fuel capacity.
So I am in the 140-150 kt bracket. If I were looking for a plane to travel with today, I’d be looking at a Mooney 201 or a TB20, both of which are solid 150-160 kt airplanes.
Compared with a boat, every aircraft is super fast It’s more the comfort IMO.
simply because it is at least 30 kts faster at the same fuel flow
Faster than a C182 
I agree with.@Peter I find range more useful than speed. But I also find the ability to land on short grass strips more useful than speed. A comfortable seat is also more useful than speed IMO.
Mogas is more important to me than speed.
There are very few SEPs that can fit all 4 preferences plus have an IAS of 130kts or more. (Note I wrote IAS because when someone says they get 170kts TAS you need to ask. At what altitude?) If we could standardise the TAS at say 2000 or 3000 where a lot of people fly then I would be fine with that.
My old Aztec on standard tanks cruised at 180kts at FL070 with 6 people and luggage on board, for a no reserve range of just under 800NM. To do that in Europe today I would be paying. €2000 + of fuel alone.
On the flip side I have seen well over 200knts GS. But then I have also seen that in a DA42 using about 40litres of JetA and hour but a little less range even with aux tanks IIRC.
But then the Aztec was happy landing on grass which the DA42 didn’t like.
Choices, choices.🙂
The social aspect of GA is the #1 thing for many pilots (and their families). So soft field performance is key, and unless you get a turboprop that means a slow plane.
Also that means short trips, so you don’t need speed.
Something to think about.
I like the TB20 combination, although nowadays I don’t normally do grass because a) it gets filthy and b) there tend to be holes etc. I would not want anything slower because for me the trips to/over the Alps are such a huge value add-on. But then I’ve done > 200 airports, never fly if I can drive in a similar time, and the nearby stuff is of minimal interest, except LFAT for meet-ups and high value getaways.
Haha, spying eyes 🤣
Pity… I didn’t spot your aircraft, parked in the grass?
PS
Flew in and out on Carson speed. Flying is such a joy, why would I curtail the pleasure by wasting fuel, producing more noise and pollution, and give my engine a harder time?
