The 486 landscape was weird. You had crippled, 386-like versions such as the 486DLC/SLC, Intel's DX4's that hit 75 or 100MHz, and clones that went up to somewhere around 133MHz (by this time the Pentiums had hit the streets, so the 486's on steroids were for budget users). And they were often given similar sounding names to the 586, to further confuse buyers.
It was amazing, and infuriating, to have your decently high-end system basically obsoleted in two generations. And, the DOS to Windows transition didn't help matters. It seems really odd in a time where you could still be using a 10 year old i7 and be just fine.