I don’t do a lot of oil painting now, but I have always had a preference for boards and panels; these were the only thing I could afford forty years ago when I first started in local classes. I find that the colours seem to stay brighter on panels (same goes for acrylics, too). In recent times I’ve also painted on MDF panels, prepared with sealant and acrylic gesso…I rather like the smoothness that this panel gives. Haven’t tried the Ampersand gesso boards, they are now available in the UK but a bit pricey.
Also have a pad of Arches Oil paper…that’s quite an interesting surface…still experimenting with that, when not into pastels.