Trading for high runes in ists?

I'm in the position where I can slowly prepare for trading my collected runes for a

Jah oh

Ber (still not decided if I should go for Enigma or Infinity).
I wonder if it's easier to trade for

Jah/

Ber if they are all in

Ist runes compared to a random collection of

Vex

Ohm

Gul

Ist etc.

I have found that most people do not want a large collection of

Ist runes. some people do, but from my observation it seems most people do want a just a massive amount of ists. its been easier for to get those

Ber's and jahs by trading my ists for

Vex or

Ohm or

Lo and trading from there, but if you can find someone thatll take 23-28

Ist go for it.