What can I say?! It is pretty much everything you hope it will be. I don't know what the pictures in your head are when you are considering this event, but it'll be close, so go with it!
I personally own a couple of Porsche 911 and a V8 twin-turbo Maserati Quattroporte, so a Ferrari 458 isn't a big distance away in terms of feel and driving experience.... theoretically. In practice, the gap between each 'flavour' of SuperCar is more than big enough to make this 458 experience well worth the effort and expense, perhaps embellished considerably by the fact that you can hammer it to the extent of your personal capabilities on a race track. It certainly isn't what I get a chance to do every day, so I bought 2 extra laps and I'm very happy with the day.
If you are a good 'everyday driver' whatever you imagine that to be but have no experience with Italian SuperCars, then the 458 will be a really BIG distance from your normal, and this will be an especially awesome experience to remember.... and brag about -- C'mon! You know you're going to!
My only disappointment is that by the end of 5 laps I was just getting into the rythm of how the car moved, gripped, and powered on that track, and like you will, I was getting faster and smoother with each circuit.... and then it was over. Hmmph! So I guess I'll have to come back for more -- I bet you do too.