Well, the biggest issue, as noted above, is that it is an AR-7.
That's a whole pile off issues (as noted above).
Because of the design, what you have a short length-of-pull stock on a pistol. Your supporting hand pretty much has no where to go but upon the shooting hand. This makes for an odd "triangle" to poke the stock to your shoulder. The buttplate is designed to optimize for the storage strategy, not for shouldering. So, it can feel a tad strange.
That strangeness continues as the rear sight is also closer to your eye than it would be with a pistol, which changes the sight picture some.
These are not insurmountable issues. They are just unique to the AR-7 and want some adaptation to get to familiarity. The package, though, does not much endear itself towards getting in the number of repetitions wanted to really get familiarity. Which tends to not endear the platform to folks.
Is it great? It can be. Is it a dog? It can be that, too. If you have the niche this fills, it will do that handily. Cool thing about firearms, it's not one-size-fits-all.