is getting this worth it? what can I expect to make per hour?

It is worth it for more than two reasons off the top of my head:

 

 

 

1) You have the ability to make your own nature runes, which means more profit when alching or possibly superheating ores. You also only ever have to worry about the GE price of pure essence, not natures.

 

 

 

2) You can make profit anytime you want. Pure essence will never exceed the cost of a nature rune.

 

 

 

I'm not sure on gp/hour. That depends on if you're using a familiar, pouches, teleports, abyss, or any combination thereof. But I'd say 100k+ per hour at least?