Robe of Archmagi and Cloak of Resistance...

[Concordia]

Do their bonuses stack?

I'd say no, my mage would like it to be yes!

Fred

[Grick]

Concordia wrote:

Do their bonuses stack?

Robe of the Archmagi: "+4 resistance bonus on all saving throws."

Cloak of Resistance: "These garments offer magic protection in the form of a +1 to +5 resistance bonus on all saving throws"

Stacking: "Stacking refers to the act of adding together bonuses or penalties that apply to one particular check or statistic. Generally speaking, most bonuses of the same type do not stack."

[Ed Wiscombe]

the resistance bonuses would not stack. They are the same type so the better bonus would apply.

[Concordia]

Thank you!

That is how I read it as well.

Fred