When it comes to valve and slide oils for brass instruments, synthetic and traditional options each have their perks. Synthetic oils offer longer-lasting lubrication and resist gumming, making them ideal for high-performance players and those that don't like the traditional petroleum based oil smell. On the other hand, traditional oils tend to be cost-effective and widely compatible, providing a reliable choice for everyday maintenance. I generally recommend trying synthetic oils for their superior longevity, but ultimately, the best choice depends on your playing style and needs.

If you are interested in trying a synthetic oil, my personal favorite is Hetman's oil. They offer a wide variety of oils in different viscosities for any situation. They also have slide oils (and greases) that are simply the best I've found.

http://www.hetman.com/products.html

Let me know if you are interested in purchasing or have questions about which of their products might be best for you, but for a valved instrument, you can't go wrong with Hetman #2 oil for valves, #4 light slide oil for 1st & 3rd slides, and #7 slide grease for tuning slides!