I first started using Hybrid when I got my Monettes. At the time, Monette recommended Hybrid as the best oil to use for new, tight valves.
After I went back to conventional horns, I kept using Hybrid. BUT, I found that before I could use Hybrid, I had to completely clean the horn, and get the old oil out of the valve casing. I use regular lemon Joy dishwashing liquid. Squirt some in each valve casing, then use a valve casing brush. As for the valves themselves, I rinse them off under warm water, put some liquid Joy in the palm of my hand, then rub the soap all over the outside of each valve. It seems to de-oil them very well.
Then, Hybrid works well. It must be something in the formula that is not compatible with full petrolium-based oils...
Someday, I may try H2Oil from Reeves, but as they say, "If it aint broke"..........
Mike