Is I-485 Quicker with K1?

[TomasK1]

Going through the K1 process right now, I was under the assumption that the I-485 process would take around a year but the processing times say up to 3 years or even longer. Someone told me that's because other visas often take a lot longer to go through the AOS process than K1 visas. Is this true and does anyone have experience with this?

[laborobnoxious]

The processing periods suggest up to 3 years or possibly longer, but I was expecting the I-485 procedure to take roughly a year. That's because, I was informed, the AOS procedure for visas other than K1s often takes a lot longer. Is it so, and does anyone here have any experience with it?