I have not driven at the track in 2 years. I have a track built s2k which is seriously the most fun car ive ever owned. Very fast and fun track car. My wife has a 2013 BRZ, e85 and bolt ons. Much faster than a stock brz but still not as fast as an s2k. Fun track car though. 2 years ago I bought a c5Z with an LS3. Nothing special, just about 40hp more than stock or so. Amazing to daily drive if you dont mind the rattles and an electrical issue here and there every 1-2 months or so. Very balanced, similar to a BRZ on a canyon road (never tracked it), great daily. Steering is not as direct though and direction change not even close to a BRZ/S2000. You will have to add bigger brakes/track pads and lots of cooling mods if you want to do more than 3 laps without overheating something. Drove it for 2 years as a daily and it was fantastic. Cant beat letting go of the clutch in 2nd, in traffic, and it just goes. Interior is cheap and like I said earlier it rattles ALOT. Just bought a c6Z with about 600hp last week. It looks awesome and is crazy fast. Had it not been for my job requiring me to take last minute trips anywhere in the world would I take it too the track? Maybe but I would be scared shitless and probably wouldnt be having as much fun as driving the s2k or BRZ at 10/10ths. Yes I bet you the C6Z would be faster at 8/10s but definitely not as much fun. The c5z, yes. Not overpowered, balanced etc but have to spend money to make it track worthy. A stock BRZ can be made track worthy with just decent pads and an oil cooler. S2k doesnt need anything except pads if you are quick.
That said, there is a perfectly trackable, very fun BRZ for sale with FlexFuel, new brakes, new clutch, tune, headers and oil cooler for sale by my wife. Oil cooler too. The plan is to sell it so we can get the funds to convert the S2k to a daily drivable car for her. Feel free to come by for a test drive. The car runs great, she just wants something different and more challenging. If you are interested, shoot me a text at seven one three, 202, four four 74. Comes with all stock parts just in case you dont like the loud exhaust. Also extra sets of wheels so you can mount your track tires.