Good stuff

Oil itself seems quite good but the straw that came with mine doesn't fit into the nozzle! I had to borrow one from a bottle of brake cleaner which made a better fit but still leaked a bit. You do not want this stuff spraying all over.

For this reason I wish that I had bought the other frame saver oil.

This is an excellent product. I am a professional bicycle mechanic with over 35 years experience that includes managing and providing technical support for a road racing team. I have used Pro Gold Steel Frame Protector on my personal number one ride. A fully custom Waterford R-33. I have also used the competing product known as Frame Saver. It also works. In my experience, the Pro Gold product dries more quickly than Frame Saver.
A little bit goes a long way. A six ounce can, the amount advertised on the can and elsewhere, is enough to treat multiple steel bicycle frames. It is a messy job, so wear gloves, old shoes, and keep lots of rags within your reach. Seriously, if I didn't do this for a living, I would be willing to pay my LBS in order to avoid the mess, but I am a bike shop guy so I don't mind. In fact, I seem to get some sort of sick satisfaction from overhauling bikes for my family.
Today's quality steel frames are expensive, and you get what you pay for, so take good care of your steed. Clean and polish your frame's exterior often. Touch up scratches as soon as possible, and whenever you have your annual complete overhaul done(should be at least once a year if you are an avid cyclist), treat the inside of your frame with Pro Gold Steel Frame Protector. This is a great product. Just like Listerine, It says what it does, and it does what it says.
No. I do not work for Pro Gold, but I do presently work for a very highly regarded shop.

Applied to the interior of my Surly Cross Check.

It's a good idea to totally strip the bike before application to ease clean up and rotating the frame.

Once it sets up on the paint it becomes quite sticky so it pays to go slowly and use short sprays to limit what leaks out.

No data on if it has prevented any rust or a control to see if it is better than no coating.

The title of this product says there are 8-pounds of spray in the container, and the product details suggest that there is enough liquid in each container to treat multiple frames. The reality is that this is only an 8 OUNCE container...about the size of a can of soda!

I have not used it yet, but I'm certain it will not be enough to treat more than two frames thoroughly...if that.

I'd recommend buying a big can of Boeshield T-9. That is what I intend to do next time.