Airsoft Gun Suggestions, Experienced players?

If the G&G F2000 is anything like the JLS F2000, you might find the sights awkward and difficult to use and it's very back heavy, as with most bullpups. The rails on most airsoft guns are essentially the same anyway. What I'd suggest if you don't like upgrading are brands like G&G, KWA, Classic Army, VFC, AGM and most especially, Tokyo Marui.

I'd actually suggest learning about upgrading your current gun because it'll be cheaper and better than buying a whole brand new gun. Get yourself some compression upgrades like a new cylinder, spring guide, piston etc., new gears and motor, a new hop up bucking, a new hop up spacer, a longer and tightbore barrel and then just use heavier BBs. If you can't be bothered to do this yourself, your local airsoft shop should have a gun tech there to do it for you. As much as possible, don't get a stiffer spring without getting durability upgrades first or else you'll break your gun faster.

Finally, don't make high FPS a deciding factor. FPS is overrated. Most high end brands actually have lower FPS than the cheaper ones to improve durability. Most cheaper brands have high FPS on their guns to appeal to less experienced people who think that FPS is the be all and end all of everything. As far as range is concerned, heavier bbs and a properly set hop-up will give you plenty. Also, trademarks and licensing are just a way for manufacturers to hike the price of their guns up.

I would reccomend asking him if he would rather have a BB gun instead of an airsoft gun because they are more durable and powerful.