We generally use "Better-than-Bouillion" unless I need something shelf-stable (like for travel/camping) and in that case I've used Maggi and Wyler's brands both.
To be clear-- this is for PA/TNA/Egg allergic DD. All of those things have been fine for her for many years.
BtB probably has some minimal XC risk with shellfish (shared lines-- though I've never verified this and there are probably some things that I am happier not knowing), and it does contain some soy (but much much less than other brands, which is why we use it-- my DH is soy-allergic). It also comes in a low-sodium and vegetarian version. We use the low-sodium chicken and veggie versions of it all the time.
DH can't tolerate bouillion cubes from a soy standpoint, so we very seldom use them.