FIS has assets that AMW does not and vice-versa, so direct comparisons are almost useless aside from using AMW to peg the PLS value in FIS, which lets you see how the market is valuing FIS' other assets.
Here's what's happening: People want exposure to Patterson Lake, so they look at FIS vs AMW. FIS has multiples of AMW's share count, so AMW provides the most direct leverage to Patterson Lake. If you want exposure to PLS AMW is what you want to own, simple as that. It's a question of leverage, period. Initially, the market was pricing AMW off of FIS... that's backwards. AMW should (and now is) pegging the value of PLS for FIS. I have no problem with FIS, but for me, I like Patterson Lake, which is why I'm in AMW.