As far as I know Frost isn't really even a manufacturer, it's just this big company that will put its name on whatever cheaply produced stuff a particular factory wants to have them brand. I think that's why there's the "Steel Warrior" line of Frost knives too, since there's actually several different ones of that name.
I have a 4-bladed congress slipjoint that is one of those "Steel Warrior" ones and it's not bad--then again it's certainly not fantastic. Other knives I've seen from Frost are just plain bad. They're not something you should really go out of your way to look for. If you see one at a gas station or something that looks okay just use your better judgement about whether it's any good based on what you want it for. Personally I think they make decent beater knives.
