I don't know... well, OK, I do know some things.
The Humvee is an ordinary Hobby Fan Humvee that they already made before. I have two from MPK in Taiwan armed with MK-19s (but haven't built any). The only "new" parts are the 20mm gun (or 25mm or 30mm...whatever). I don't know how much Hobby Fan charges for these new parts, but someone can use the Italeri 25mm gun in the accessory box (although someone said it's inaccurate).
Also, the rollcage really is specific to Taiwan ROC. The closest contender is Jordanian SFs, but their rollbars are different in the back (Concord's SOJ has a photo).
In terms of firepower, I doubt this gun can (or should) do more than single shots. The US Army never adopted the 25mm Bushmaster on the Humvee (Tamiya kit) because after a few shots, the doors and frame cracked or fell off. The recoil and vibrations were too strong (Army captain told me) although the joystick and TV inside the Humvee 25mm were pretty useful. As you can see by the rollcage, the bars don't seem strong enough to support rapid-fire. Granted, that was 25mm, so I really don't know about 20mm.
As such, this is indeed a recon version with the 20mm cannon as self-defense. It is not a guntruck, not a firepower truck., and not a shooter-scooter.
I'm not jinxing or dising this kit. I just want to point out what the kit is. If you're looking for Humvee firepower, I say a M2, MK-19, minigun, Dumvee, or TOW would be more firepower than a 20mm single-shot cannon mounted on a Humvee. So make sure you know what you're buying before you do.
While this kit may look cool, it's can't or shouldn't act as a guntruck. The Humvee's just not strong enough.