I've never bought the small bottles.
When I split large bottles I used PP containers, they have a good chemical resistance and are common and cheap. I used screw top 500ml tumblers from Wilkos 59p each. Four years on there's been no problem. I have some chain oil in Polysu bottle and some motorcycle oil in PVC, so there's a choice.
I never thought to ask if it had a shelf life. I assumed as it's mineral oil that's been in the ground for millions of years it'd last indefinitely. I've had a look at every oil container I've got including Rohloff, none of them mention a best before, or a manufacturing date. I wonder what happens to it after five years. I split mine four ways, so I still have plenty left. A litre is enough for around 70 changes, I'd imagine that's more than many workshops do in a five year period.
One thing to be careful about is mixing the gear oil before splitting it, I don't know the components but they do separate. A shake may not be enough and the small top stops you giving it a stir. I poured mine out and noticed the third one was different to the first. I put them back in, stood it upside down overnight, shook it in the morning and it was OK.
You’d think that Thorn if not Rohloff would recognise the demand for a quantity between 25 and 1,000ml. I’d bet a quarter of a litre sold at half the price of a litre would sell well. Maybe they make too much on the small bottles.
