I’d bet a tenner that the Osmo stuff will be better than the Ronseal stuff.
“anti-bacterial” is probably bollocks anyway…
Oh, and for t’others, how finely you sand the wood depends on the species but as Stoner said above, certainly no finer than 120 grit for temperate hardwoods (Oak, beech, maple etc) and no finer than 80 grit for tropicals -iroko, etc. If you sand too finely, you’ll, in effect, “seal” the timber and the oil will only penetrate to a too shallow depth.
A good idea is to sand, then vacuum the surface with a brush attachment, then tag-rag it with a white spirit soaked cloth (you’ll be surprised at how much dust still comes off). You’ll have to wait a while for the white spirit to dry off, but it’s worth the effort.