Seriously, this is getting old.
I made sure to tell Singtel exactly why I switched. Not that I think that'll change anything, but it did feel good to let them know they lost a customer because of their poor IPv6 support.
My ISP does offer 2 Gb/s (the fibre modem has two 1 Gb/s connections) but that's starting to get ridiculous. A mentioned above, at those speeds the problem are usually with other parts of chain, like your local hardware's ability to actually process the data at that rate.
One thing that illustrates this is that after I upgraded to 500, I realised that my existing router wasn't actually able to handle more than about 250 Mb/s, so I went and bought a more professional router and all of a sudden I could saturate the link.
"You need tender loving care once a week - so that I can slap you into shape." - Ellyn Mustard