I flown VFR to Antalya, Odessa, Nordkapp, Coventry, Dinard, Bilbao, Seviglia, Malta in the past, starting from Rome, 90% without GPS.
I keep my Warrior 161 mainly for long distance flights, including Helsinki (1200 mi) each year, Warsaw and Oslo, all VFR. I’m not IR material and neither is the aeroplane! I need plenty of time and flexibility for these trips, but rarely have to break a commitment and always get there somehow, even if it is a short detour on a very nice Baltic cruise ferry as happened this summer. I often wonder about how much better my dispatch rate would be IR but find in many cases that icing, or lack of oxygen, or 161 climb performance, or strong headwinds, uncomfortable turbulence, thunderstorms etc, not to mention lack of IR currency, would level the playing field somewhat. Another factor with a -161 is that almost anything that can go wrong (and it will!) can be mended by a local mechanic, or by myself with a fairly resourceful tool kit.
In the US I fly a 172SP, always VFR, and this summer made Savannah Georgia from Prescott Az (1700 miles each way) with a stopover in Nashville and in January a grand tour of the winter mountains up to Salt Lake and the Rockies from Durango down to Albuquerque also about 1700 miles with a stopover in Vegas.With the 172, ditto the comments about maintenance – I now have a full house of every one of those annunciator warning lights (at different times, obviously – so far)!
I’m very fortunate in being able to make these trips with understanding family and customers. I fly for looking out of the window and never cease to be amazed by the astonishing vistas that drift by outside. By the way, flying in Scandinavia is almost as easy as in the US, but of course much, much more expensive!
Used to applies for me as well. Simply lack the time now.
Longest one day trip was LSZH-LFLY-LFMP-LFMV-LSGG in one day with a Cessna 150.
Longest route with the Mooney was going to Bulgaria in 2011.
I went coast-to-coast in the United States in a VFR only Cessna 140. It did take a while! When I visit the US, I still do some reasonably long VFR trips.
I’ve only done 200nm or so trips in the Auster though, a situation I’ll some time rectify…
I flew from EDLN to EDNX a couple times, round trip about 550NM, mostly with one day in between.
Then in September from EDLN – EDNY- LOIH for a pickup, and then through Inntal and Brenner to LIQS, all in all about 700 or so.
Back a day later, LIQS – LOIH, then the nex day LOIH EDLN. And many other flights of 200-300NM, i.e. to Slowakia, within Germany and the Netherlands.
To do long distance (>500nm) flights you need several (at least 2) days. This is not so easy to achieve for a lot of people due to family and/or work constraints.
Additionally, while some people only (or mainly) fly to travel somewhere, in my experience much more people within the PPL VFR community wants to fly just by the sheer pleasure of it. I’m one of those, and honestly a flight over 3h starts to seem boring to me, specially during the flight back if you have to flight back on the same day. So I make longer trips occasionally, but enjoy a lot just bimbling around or doing trips of less than 500 nm.
Because of these facts, probably the percentage of more than 500nm flights that VFR-only pilots do is not so big.
The person which can make trips of several days, and that enjoys more with the travel than with the flying, probably flies IFR almost all the time.
I think for long distance VFR it helps a lot if one can go VMC on top.
I did all my long VFR trips like that. And often at max altitude permitted by ATC. So FL129 over the Alps in Switzerland 
FL140+ in Spain, over the Alps in Italy, Croatia, etc.
But VMC on top is tricky unless one is instrument-capable. At the UK end, the IMC Rating works brilliantly, not just to legalise it but also to train the pilot for descending through, ahem, holes in clouds which is by far most safely done over the sea i.e. to coastal airports. Otherwise, you need to be very sure of the destination wx.
As regards the original Q about percentages, I am sure it is very small – of the order of 1%. But a huge % never fly beyond say 50-100nm, so the size of any group that goes anywhere is going to be tiny.
the order of 1%
My guesstimate of VFR only aircraft pilots active on this site may be more like 25%? Although overall given the large number of pilots who only fly a few times a year to keep the licence current, perhaps lowish single % figures?
Number participating… number reading… I don’t know. The two groups are vastly different. Over 1000 real pilots read EuroGA daily, every day. No idea who they are but from what they read they obviously find it interesting (5-7 pages per visit).
A couple of people in our and neighbouring clubs organize long trips once or twice a year, spring and fall. All VFR so UL can join in the fun.
Spring 2015 was ESMK EDBH EDBN EDAZ EDAY EDQD EDMV EDBM EDWQ EDXR ESMK. 5 airplanes.
Fall 2015 was ESMK EDXR EDWO Bremerhaven (closed since, close to EDWT) ESMK. 4 airplanes.
Spring 2016 was supposed to be ESMK EDDR LFRF and back. Due to weather we got stuck in northern Germany, but still managed ESMK EDWF EDWR EDXW EDAY(for half of the fleet)/EDCG(for the other half of the fleet) ESMK. 5 airplanes.
Target for spring 2017 is ESMK LFLB LFKC. So far 7 planes planned.
It’s clear that being this close to Germany, with its high quality beverage and frequent airport restaurants, are good reasons to cross the Baltic.
