Random or not, there is good and bad everywhere, here are few observations of mine on oil painting products.
I’ve found Da Vinci Kolinsky Marder red sable brushes to be of very good quality, long lasting, and affordable, they do exactly what a good brush should. Brights and filberts suffice for my technique, for detail I use Winsor and Newton series 7 rounds. I prefer size 1, size 0 is useable but brushes of this size have no strength. As to stiff haired brushes, I’m not too fussy, although again I have found Winsor and Newton to make good hogs hair brushes.
One particular item I can’t do without is lead white, it has become increasingly important to me as I’ve painted skin more and more. It has a luminescence to it and is absolutely not chalky. One lead white to avoid is made by Vasari, I haven’t tried their other paints and wouldn’t as my experience in dealing with them by phone was a joke. What a shite, fake product, fuck you Vasari, your ‘lead white’ is a joke. I called them and was greeted by one of those phoney posh American accents, where the idiot tries to sound colonial British, this person had the pretentious attitude to go with it, I should have stopped right there. I ordered a tube of their expensive shit, lead white and have never been more disappointed with a tube of paint before. The paint had separated so much that I had to decant it, re-mix the oil with the remaining paint and put it in another tube. The paint yellows within THREE weeks, this is unacceptable, I couldn’t recommend this goo for painting your house. Expensive white treacle. Avoid like the plague if you are a serious painter. Blockx lead white on the other hand is wonderful stuff.
I don’t often use mediums as I paint the C.S.O. method with sun thickened linseed oil, chalk and egg. I do occasionally though and I find Alchemist Mediums to be very good, although the amber varnish will, yellow tint whites. It isn’t suitable as a finishing varnish for a painting that has a lot of white in it. The mediums are taken from the de Mayerne manuscript, so are historically accurate. Painting a large painting with these mediums would be very expensive but they are excellent for small paintings, portraits and the like. The optical effects offered by these mediums are easily matched or surpassed by the C.S.O. method as it too offers painters who use extensive layering quick results that give real depth to the paint finish.
As to tube paints, I favour, Michael Harding ,Winsor and Newton, Blockx, Talens Rembrandt series, Daler Rowney, Georgian series (cheap but consistently good) and Old Holland. There are a lot of good manufacturers out there but I would avoid Vasari.
I buy most of my products from https://www.jacksonsart.com/ they offer free postage to Europe on orders over £100.00, they have just about everything, though are not brave when it comes to selling the more toxic products. The complete opposite is the silly attitude of greatart. co.uk who if you try to buy something from them and have it sent to France, they will refer you to the French website where the same products are considerably more expensive, fuckin’ stupid!
I buy chalk, cold pressed linseed oil, glass powder and a few other items from the massive German art supplier http://www.kremer-pigmente.com/de. I make my own sun thickened flax oil.