Are both using cement board and sheet membrane? Is one foam board and the other cement board w/sheet membrane or foam board vs liquid applied? Will the base be foam or mud?

Need more info for comparison.

I will find out and get back to you. Thank you so much for responding! Means a lot.

Our favorite is Laticrete Hydroban Backer Board which is made from foam with waterproofing on the outsides. Its a bit stiffer than Kerdi board. There also are some installation advantages to HBB,

I'm guessing the Hydroban Cement board is Hydroban Foam board.

Kerdi can be either Kerdi membrane over cement board, or Kerdi Board, another foam board.

If foam board versus foam board, in the hands of a competent installer, both will give you excellent results in a residential shower. It's simply in the installation details.

Board versus board, I lean towards Laticrete's Hydroban Board over Kerdi Board. Nothing really against Kerdi. But I do favor HBB over KB.

If you prefer one installer over the other, I'd go with your favored installer and whichever product they use.

FWIW, my master bath shower is Kerdi sheet membrane over cement board. Been in 20 years...no complaints.