SGS (Long) or GS (Medium) SLX RD?

wilbo83

Looking to buy an SLX 2x10 groupset and I am confused about SGS vs GS rear derailleurs. The SLX chainset is 26/38 and I am considering either a 11-34 or 11-36 cassette, but have no idea which derailleur each setup would need. Using a formula I found, the capacity of these give 35 or 37 respectively. Any advice welcome.

cooldad

Shimano techdocs will have mech capacity (or sellers website should)

rockmonkeysc

Medium cage