I've got an Isollette, but as already mentioned they have two problems, grease that sets like concrete and bellows that nearly always need replacing. There are many, many other folders around with very similar specs, that don't have these problems. A CLA'ed Isollette with new bellows would be a fine folder, but a Zeiss Ikon folder of similar spec would be available at much the same price as the Isollette before the CLA, but the Zeiss folder might well function perfectly well with little or no attention and the original bellows.
In 6 X 6 I have a V. Perkeo (sticky shutter and the focussing was all wrong, but probably not typical), an Isollette, three Agifolds, a Kodak 66, two Zeiss Ikon Nettars, a Nettax and an Ikonta (Opton Tessar).
IMHO the four Zeiss cameras are by far the most reliable and have stood the test of time better much than any of the others. The British Agifolds are well built, with rangefinders, but a bit big and clunky and about twice the weight of the others!

The Kodak is similar to the nettar but just not quite so well finished. The Perkeo should be nice, mine was a bad eBay buy, but has a habit of losing it's covering...
A small detail, but one that drives me nuts with nearly all folders, including the Isolette and the Perkeo, is that there is only just enough clearence in front of the lens to close the door. With the Zeiss Ikon cameras there is a fair bit of space... s
o you can leave the filter on the lens! Sounds like a minor point, but so much more practical when out and about.
