Can't speak to the Armstrong board. But I've got a 6'1"x26" Kalama. (wide DW version).Combined with (getting) progressively better at 'rocking' the board with Riggs's pop up technique certainly makes catching things easier. I find the board relatively stable, all things considered, but watched a friend get humbled by not being able to even kneel on it in choppy water.
when I was shopping prior to order I was talking to guys at the shop in Oregan (big winds ?); they had summed it up as Kalama-less stable earlier release. FG-more stable slightly later release. They are one of the few places I found that stocked both and could give a direct comparison.
long story short. I'd recommend it if you can get a used one at a decent price. Worst case it's not any better and you turn around and ssell it.

I couldn't get it up on these tinny unbreaking rollers on my old board. It certainly makes a difference.