Miko is right.
In my opinion the UC2 stinger is the coolest mini-gun/stinger weapon in any Unreal game up to now. When I read it's going to overheat if you use it for too long I thought to myself, please don't. Not in an Unreal game. Then I read on and learned that it only gets better the more it over-heats. How badass is that? When in other games you have to let your weapon cool down when it overheats, in UC2 that's the point where you start to rock with it.
Just the concept has badass written all over it.
The homing shards were cool too. Good enough to squeeze in a bit of damage into an unsuspecting target with auto-aim but crappy enough so someone who saw them coming could evade them. Not to mention reject them. If you had no target selected they followed your crosshairs which enabled some mean manouvers too.
I think Epic simply were afraid of putting homing shards in the pc version because everyone would be screaming "consolization".
Come one, you know you would!
So instead they went with the "skilly" version and made them pin-point accurate straight firing. A bit boring if you ask me, but still miles ahead of the lame miniguns in UT99 and UT200x.
Why they didn't keep the overheating is beyond me.
The Unreal 1 stinger was cool too but I think it's altfire is now the domain of the flak cannon and it should stay that way.
To differenciate the weapons in UT3 further I think it would be cool if the stinger shards locked on to people
slightly and followed your crosshairs. Following crosshairs as alt-fire and locking on to people as prim-fire plus alt-fire. That way it wouldn't overlap with the link-gun alt-fire.
Someone posted they are different enough and that they are used for different purposes already:
Yes, they ARE different. As different as an uzi and a kalashnikov in most other games, but that's not different enough for Unreal,
imo.
The link primary and the stinger primary overlap a bit too but the link-gun already has this unique function that it can be used to link with other people's link-guns and to heal friendly vehicles, so I think that's alright.