Ok it's only ￡1.60 but i'm a bit of a miserable sod so just wanting to know if it's worth getting.

I would say its definitely worth it. It adds a few new types of weapons, GRA versions of older weapons, several unique weapons, new types of ammo, and several new types of explosives. So yeah, i'd say its worth it. Here's a complete list of everything in GRA: http://fallout.wikia.com/wiki/Gun_Runners%27_Arsenal#Items

Cheers i'll give it a go.

If you have all of the four regular DLC's I don't think it is all that necessary. There are so many weapons in this game that it's hard to add anything that breaks new ground. None of the GRA weapons really add much to the game; it's mostly the variant ammo that's interesting.

It does seem like there's more rare ammo available since installing GRA, though.

One of the quiet things GRA did was revamp the vendor inventories. There's a ton of new stuff that some of the "less than impressive" vendors now carry. I now regularly farm the traveling merchants for mods and plasma 40mm and 25mm. They're a great source for that. There were quite a few things Josh tweaked with this and I'm still finding new stuff.

-Gunny