Got a +2 from Vortex for a 520 chain. Sprocket was fine, but I went -1 on the front as well and didn't care for how much it changed my engine speed at my commuting speeds, so I took it off. Went with another Vortex in stock size and 520 pitch and I'm much happier. If you're going to change chain pitch and want my Vortex (it's plain silver, IIRC) pay for shipping and send me a decent maduro cigar and your address and I'll send it to you. If you want to keep the 525 chain, you'll have to order the sprocket from Vortex. I'm very happy with Vortex. Price was decent, service was excellent.