I kind of have a love/hate relationship with these things (High Speed Red). On the one hand, Tifosi's specs on their light transmission and darkening are complete fabrications from what I can tell. Using a luxmeter they have a VLT of about 50%. At 3,000 lux I can put these lenses over the sensor and it's around 1500 lux to start with, and the best figure I get is around 40% transmission (e.g. the lenses block 60% of light). Tifosi claims 35% at lightest and 15% at darkest. Totally not happening. And I can't tell that these things *ever* dim or darken in the light, even straight out of the case. They always look relatively clear (if red-tinted).

That said, the high speed red color is quite effective at making things look sharper. They're not polarized (which is either good or bad depending on what you're doing), but the red color does blue light rejection very well and they act like polarized lenses in that regard, without the funny optical effects. And the all-plastic frame, even though it feels supermarket-sunglasses cheap, is actually very resilient and supple and they stay on your head like glue. Without feeling like they're clamped on your head.

But that easy plastic build, including the lenses, means that the lenses get scratched if you so much as look at them menacingly. I've tried to take care of these like they were a $500 pair, keeping them only in the case when they're not on my head, and they still have vision-obscuring scratches within a month. I loathe even having to clean them for fear of scratches. This is now my newest pair (I said I love them right) because the first have just become a damaged mess. But I know that these are effectively an annual sunglasses subscription as that's about how long I can go before the scratches from normal use and the occasional drop/scrape against the car dash make them aggravating to look through again. I wish that replacement lenses were cheaper. Right now it's $10 extra to just re-buy the entire set with frame, case, bag, and wipe, over just buying a new lens. It seems silly to design the product to take interchangeable lenses then price the lenses at nearly a whole new unit cost.

Overall, if you want polarized-like performance without polarized lenses, don't mind everything being tinted (or if you're a fan of the old "blue-blocker" lens fad) then these might be a good choice if you can treat them like royalty. If you're just looking for photochromic sunglasses or you aren't kind to your sunglasses, you might want to try something else. At the very least, I can still buy four of these for the price of a similar pair of Oakleys, even if these don't perform as promised.