Gt's arnt traditionally the lightest frames either so I would question a sub £500 bike coming in at much less than 28-30lb I can't imagine your meta weighs much more than 32? So how are you working out the big weight loss?
Bike radar says - "Weighing in at 13.7kg (30.25lb), the Aggressor is a bit of a bruiser"
To be honest your probably better getting lighter wheels etc for the meta and swop them over for the long xc rides Personally I would rather do such on a 32lb full Susser than a 30lb hardtail
You're pretty much where i'm at with them thoughts. Although with the minor part about the wheels, i spent £200+ on them (£600RRP) so they're not coming off anytime soon. Although for such events i may run a pair of Rocket Rons for example.
The MEta comes in at under 15kg... about 14.6 i rekon.. so the weights are not THAT different enough to make a huge difference unless i start throwing a Grand at a much better HT.
It seeems a shame not to take advantage of the C2W scheme again and again.. but also... no point buying something of no use.