Or McMaster Carr. RS, with it's laggy backend (I assume, as their recent UI shinification didn't change it: it was bad before) could learn a lot from them.
Then again, McMaster Carr want you to use an app on mobile and the new RS site works on mobile quite well, with the lag more hidden by the inefficiencies of mobile browsing in general.
I personally find it very easy to parse visually, font size is ideal, no inline images or post voting or overbearing profile/social BS on the forums, it's peak late 90s design and (without sounding too elitist) probably helps attract the crowd they want due to that.
Fast, functional, responsive.