Resist Runes: obsolete or OBEYso1337 ?

[Delayed]

I had them 3 @ lv 4 each.

I removed them to make some space for eventual ssa, cd, dr runes.

In my bm2, as a GL, i can gain passives which gives me up to
15% knock back, stun and down resist.

My question is:
Shoud I get the Knock Back one later on? So that I can easily use my bm2 in war against FA, FS, BL in BM2, WI if using cannons.