OK I'm going to stick my hat into this discussion at long last.
So does the update suck?
In my opinion no, it doesn't. Its still not 100% right, but its tweaked a few issues from before and improved on them, but its also thrown a few new problem to light as well.
Now first off, one of the biggest discussion points here has been around the subject of grip levels, are they too sticky, etc, etc. Well I have now spent a long of hours with a lot of differing cars and a lot of tyre choices. The N grade tyres still offer pretty much what I would expect in terms of straight levels of grip, with grip increaseing as you move to S and then R grade tyres.
I will be quite honest I don't have a single problem with how much grip is offered by the tyres at all, my issue is with what happens once that limit is reached.
The N grade tyres have almost no progression to them once the limit of grip is reached at all, you go straight from grip to no-grip, they are not progressive in any way at all. Now real world road tyres are designed to be as progressive as possiable, this is at the expense of outright grip, in addition road car suspension is designed to highlight this. The main reason being its quite simply safer for any loss of grip to happen in a progressive manner.
If you were to look at tyre curves for a road tyre you would see they drop off quite sharply when the slip angle limit is reached, which results in a rapid drop into understeer. Oversteer could then be forced by exceeding the rear tyres limit with power, but it would be understeer first as the dominant handling trait, with oversteer something you transition through.
The following graph shows examples of the kind of curves you get for road biased tyres, and shows the rapid drop quite well...
As tyres get more 'race' biased they tend to increase in terms of overall grip and they tend to drop off less as they exceed the limit. This gives very high cornering speeds and a much lower understeer tendancy when the limit is reached, making the car more responsive but trickier when the limit is reached.
The following graph shows F1 tyres, and the red line (lateral force) quite clearly shows a much shallower drop-off.
Quite simply GT5
after the update has this totally back to front, the N grade tyres have almost no understeer characteristics at all for RWD cars, even increaseing the steering angle gently doesn't work with an almost immediate oversteer balance the moment grip is lost. As you move to S and then R grade tyres you get a lot more understeer and a much slower and more progress loss of control before the car switches to oversteer.
So while the overall grip levels are around what I would expect them to be, the behaviour of the tyres once the level of grip has been exceeded is wrong. Over the limit road tyres are far more snappy and prone to oversteer than race tyres are, which is just plain strange to me.
Give me more time and I will try and add to this as I can, but these are my initial thoughts.
Regards
Scaff