Back to if 16gb is worth it: If your spending £500+ on the sub system, then for under £50 an extra 8gb must be worth it.
Even if single applications won't use it, then Windows 7 prefetch will use a fair amount of the rest, files buffered into Windows prefetch will access faster then any SSD you can buy.. On my rig with 16GB I've seen at little as 250mb showing free.
If you can afford purchase 16GB at the same time, this way you know it's matched memory, and likely from same batch.
Even if single applications won't use it, then Windows 7 prefetch will use a fair amount of the rest, files buffered into Windows prefetch will access faster then any SSD you can buy.. On my rig with 16GB I've seen at little as 250mb showing free.
If you can afford purchase 16GB at the same time, this way you know it's matched memory, and likely from same batch.