The EcoPRO-2 can fix deep scratches, it is simply a matter of repair cycle time. 

The technology works by taking small amounts of polymer off at a rate of about 1 micron a minute.

The factory settings are for a 30sec cycle, and additional 60 sec and 2 minute cycles will deal to 90% of damage no problem BUT a 360 "ring of death" as it is commonly referred to is a deep scratch. Sometimes up to 15 microns but most are about 8 microns deep. 

This means that the EcoPro-2 must be working on the disc for 8 minutes if it is an 8 micron scratch...a common miss-conception is that if the disc still has the ring of death after 4-5 minutes of repair then you cant fix it...THIS IS NOT CORRECT... visually it is hard to tell that the EcoPro-2 is getting the better of the damage but it is ...just keep going because the EcoPRO-2 is a FLAT repair machine so you can just keep repairing it until it is fixed. 

We have deliberately scratched a disc in our workshop with a compass and successfully repaired the disc back to new. 

Finally, if you think you are going to repair the disc too much ...think again as you have 300 microns to work with... essentially you can repair a disc over 80 times and it still work!