The springs on this chart are Polaris springs with Polaris part numbers.
The EPI springs are not to far off on some of their specifications but keep in mind that the compressed length is different on the two charts. Polaris calls out a 1.19 fully compressed length and the EPI are compressed to a 1.25 inch length. This will give a different reading even if springs are identical.
When buying aftermarket springs and weights you must be aware of what you are buying and realize there may be a difference in performance from how the factory parts work.
I you want the clutch to perform the same as when it was calibrated from the factory then I would buy factory parts, if you understand clutching and are comfortable tuning the clutch then aftermarket parts can be made to perform as well or sometimes better than factory for some applications.
Again read the specifications and realize what you are buying.
Breaking free from the thoughts in my mind