haha yeah. In the wet i wouldn't even attempt to floor it. They were bad enough in the dry and the tyre's were really soft. The G60 was running about 220bhp, so might be different for a polo but then again, 200kgs lighter and less tyre surface area.
I personally see nangkangs as a budget tyre, i personally wont ever use them. You might find they are ok.
If you can get hold of the proxies t1r's then i'd go for them. Best tyre i've used, but them A539's are ment to be good but they are a little more ££ then the toyo's.