In my experience a 1.5-2 HP 26-30 gallon compressor will generally do as much as a 3 HP 60 gallon. My first air compressor was a 3HP 60 gallon. When I moved and lost 220V in the garage, I sold it and replace it later with a 2HP 26 gallon. I couldn't tell the difference except the compressor would run a little more often. Big deal. Past basic impact, ratchet, and tire filling, you need to be looking at a 5, 7.5, or 10 HP dual stage. I'm talking if you only have one. I realize there are special cases where a 3 HP may be helpful as an auxiliary source or may fit some specific needs, but I haven't found one. As my air demands increased I upgraded from a single 26-30 gallon to 3 of them (bought cheap) but always struggled and the noise was another issue. Today I run 2 x 5 HP Champion R series with air storage at 180 gallons. For basic use I can go a while before the compressor will kick on. If I'm using air hungry tools they both run and keep up. The slow speed the Champions run at is easy on the ears. If the compressors are in a separate room noise wouldn't be an issue. We have guys on here running pancake compressors, others making duplex 7.5 HP compressors, and others who work at factories or plants where there is "unlimited air" so this forum cover a wide spectrum.