Turbo spools up quicker and builds boost easily. Went from stock wheel at 20 psi max to billet wheel and 26 psi. I also did a turbo rebuild, up-pipes and Banks BH wastegate, so I can't say how much benefit is due to the compressor wheel. With the upgrades I pulled a 5th wheel up a couple of long steep grades at 10 mph faster than I could with the stock set up. The whistling is noticeable but not so bad that it becomes annoying. I debated between the WW2 and Riffraff's wheel, I don't regret getting the Riffraff wheel.

Great quality, impressive power gain. Slightly noisier than stock which I prefer.

Wow, very noticeable difference. I can actually hear my turbo spool up now. As advertised with regards to increase in boost, spools faster, and actual increase in hp & tq. The quicker response at the pedal is very nice.

Quicker spool, lower egt, tiny bit better mileage. Went from 15 psi stock to 22.5 psi paired with a wastegate controller.

Love it! No more surge. Perfectly balanced. The best way I can describe the sound is that it is no louder of a whistle than the stock wheel. The sound is oddly... soothing lol. It reminds me of the turbo sound of the Cat 3126 in the old bluebird school buses (all of you who went to HS in the 90s and 2000s and rode the bus, will find this sound strangely familiar). I would be fine listening to this wheel all day.

Installed this wheel as part of a turbo rebuild that I did with the up-pipe replacement. First impressions are awesome. I have never run an aftermarket wheel but I am happy with the performance so far.

Worked great eliminating compressor surge.

This wheel looks and works great. Quality part from Riff Raff. Sounds good too!

Best wheel on the market. Faster spool, and less smoke after install. Paired with the awesome customer service and fast shipping from these guys and what more could you ask for?