130kph for big blue ship (on public road, 10kph over limit so sue me) and sporty car of mine it is little under 200kph, but I have done only 160kph as track has so short straight.
I think that speeding issue is over hyped on public roads, however there are places where people constantly drive too fast, that is 80kph and lower limits where these things happens and lower the limit more people drive too fast. For example 30kph limit is something nobody is driving, 40-60kph is speed usually.
But when moving to roads that have 100kph limits and some roads with 80kph limits there exceeding limit by 20kph is not a big deal imo, more it matters how car is driven, well it is lot same for lower limits but usually those lower limits are there for reason.
However as laws are what they are, they need to be followed so I'm causing traffic jams by driving not much over limits...