During college I purchased Grumbacher and Windsor and Newton oil paints. I don’t think they had student quality paints in the late 60’s. As I returned to painting a few years ago I continued buying Windsor and Newton. This year, I decided to upgrade a notch or two and invest in Gamblin oil paints. You can get discounts on e-bay, especially if you buy the larger size tubes. But mixing it up is ok. Just learn the difference between the colors and brands. I still have a tube or two of the Grumbacher. Oil paints last forever, unlike acrylics. If you happen to see any in a flea market, snatch them up. You might find a brand of paint you never tried before for practically free. I bought an old wood painting box with paints and a few brushes for $20 on Cape Cod. The brushes were destroyed but the oil paints were in still good and worth $40 or more, Included were some London OIls and colors I had never used before.