Well I've had these on for 3 days now and I must say I'm very, very impressed. Only using them to scrub them in a little before track use but I'm contemplating keeping them on as road tyres as well for the summer at least.
The following review is going from Toyo T1R's as a road tyre:
Pretty much every aspect of driving has improved - cornering, braking, acceleration, ride and overall grip. The sidewalls are stiff, my local tyre fitter said they were harder to fit that R888's! It took him over an hour to fit them and apparently they were very easy to balance un-like some track tyres (remoulds for example can be a bastard).
Cornering speeds are much quick as the grip is just constantly there and turn in is much, much sharper due to the stiff side walls. I also find that braking is much more consistent as with the T1R's, the rear used to lock up on harsh breaking causing it to step out - not really a problem as you get used to catching it, but its far nicer to drive now. After giving them a good blast around the lanes in the evening (the day before with the T1R's and Saturday evening with the Federal 595 RS's), the difference in grip was extraordinary!! Okay, road noise has slightly increased as once worn, the Federal's tend to pick up quite a few stones however all decent semi-slicks will do this.
I was also impressed with the 8mm of tread compared to the R888's and A048's 5mm, meaning they should hopefully last a fair bit longer. At the moment, I feel they are easily on par with the Yoko A048's I used to use on track (will need to give the Federals a good blast at Oulton to fully compare) and they are in a different league to the Toyo T1R's. I would recommend these to anyone - okay I did manage to get them for £65 a tyre an it has increased a little. But for £277 delivered then fitted (I pay £2.50 a tyre), £287 full fitted is very good value for what your getting. Your saving over £130 for R888's and £150-£180 over A048's!! If your looking for a reasonably cheap or cheaper track tyre than the larger and overpriced brands get the Federals. I understand I have not yet used these on track but I've got a day booked in May where I will give them a good run for their money however the reviews online say they perform excellent on track so it should be quite a good day. Just praying its dry now

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