Recently, many Weapons come with a factory-mounted powered slide mount (1) - but which 1 slot mods are worth paying an additional 3500nY (and can be reasonably be mounted on a slide mount)?

Smartguns and laser sights.

Seems like a Waste to me.

Yeah, just pay $300 to have the smartgun integrated.

7 modslots is 7 modslots

Sure, but the "internal" smartlink that you put there costs another 3500nY more

You can buy smartguns with integral Links standard, and that therefore take up no slots. *shrug*

While true, you don't have to use smartguns in that powered slide mount.

All guns have 6 modslots.
A gun that comes with mods preinstalled doesn't count towards that limit of 6.
So a gun that comes with a stock powered slide mount effectively has 7 modslots for free.... PLUS all the other options its model may or may not have.

The smartlink is just an example of what you could there, it could really be pretty much any mod.

I'd like to know where the number 3,500 came from. "Many other" guns don't all cost 3,500 .

From the Realm of the Imagination of the Developers....

with a Dreamy Dance
Medicineman

Gun Heaven 1:
M4A1 (w/Slide Mount): 3850Y [w/o: 625]
QBZ-14: 4625Y
Ultimax 150: 9600Y
Runners Black Book:
Izom RP-63A: 5100Y
Gun Heaven 2:
Shiawase Arms Light Tactical: 1050Y
Shiawase Arms Heavy Tactical: 2800Y