So Icelantic is built by Never Summer, who never mentions Icelantic on their website, and RMU is built in the same something. Ski brands that have their skis made by another manufacturer do not inspire my confidence. It's a pig in a poke, a stab in the dark, a crapshoot. Who's ski is it? Guess some of these companies are just middle men, in for the mark-up on someone else's work and brains. Ohh, make it this shape, give it that rocker, and jua-la, it's a miracle, a ski designed from bullshit, and we'll call it: Apostle.
Neversummer has an excellent reputation for pressing quality boards and skis. I skied Icelantics when they first came out and was very happy with them. Design and quality were peachy. IMO their issue is not that their boards are pressed by Neversummer, but that they have fallen behind the design curve IMO. If you like their designs, there is certainly no reason to hesitate due to quality concerns.
Many, many brands contract out for all or part of their manufacturing because they have capacity to do so. Many sub out all or part of their builds to those with capacity. That is basic economics in today's world. Elan seems to build for half the universe. K2 has been known to do work for others. Heck, Praxis builds for H20 and Worth --- and good luck finding a more carefully crafted ski... (yes I am a Praxis fan)