UPDATE
Although I'm loathed to concede that my Netgear GS608 is the reason why I'm getting a massive drop in performance, I think I need to start considering a new one.

First off, before I frisbee the old one - how could I check if it's really it on the blink? They're such simple devices. I imagine there's software out there to monitor/measure throughput?

Secondly, what's worth buying? I'm not network-savvy enough to use a managed switch, so I'd be after something simple again, with 8 ports minimum. Integrated wireless wouldn't be essential (we've a standalone wireless router, but that takes up a port, so maybe we could retire that with an integrated unit)

UPDATE

After a bit of a whinge to customer services, Virgin have sent me a D-Link DIR-615, reccomending I put the Super Hub into Modem mode, and run the wireless, and wired, from that.

On first impressions, I was pretty chuffed that I'd gained an additional lan port - and a more capable wireless that can actually deliver signal to all parts of my house,

Speedtests suggest that something's still not up though. Wired directly into the (gigabit?) port of the SuperHub I get around 80Mb on speedtest, but wired to the Super Hub via the D-link, speedtest doesn't go any higher than the mid 40s.

Curious, I looked up the D-link online, and found the lan ports are "only" 10/100. Could that be a limiting factor in why I'm not seeing the same speeds as when I'm connected to the Super Hub? Does this freebie D-link only confirm the Super Hub was/is rubbish, and that buying a more capable device (with gigabit lan ports) was always on the cards?

Either way, further tests seem to have concluded that my netgear GS608 is in some way bottlenecking connections, (by simply putting it inline between the Super Hub and the D-link speeds drop) - and the four (10/100) ports of the D-Link still aren't enough to get all of gear back online - so suggestions for a reasonably priced new unit would be greatly welcomed.