When buying carpet for your home I've found through years of cleaning and installation that Nylon carpet , with at least a 6 lb. carpet pad , will clean & wear the best over 10- 15 years of use.
Polyester carpet does not clean nearly as well and is subject to
shading wear ,a condition which the carpet fibers will set one way
in random waves ,giving a dark-light hue that gives the appearance of dirt.
Carpet density is key in the life of the carpet regardless of style
(plush, berber, level loop ) ,along with a 6lb - 8 lb rebond pad. Any pad over 8 lb is overkill and a waste of money.
Always make sure your carpet is power stretched (mechanical tool)
when installed ,seams are sealed ,and keep any scrap for future repairs . Most big chain stores will NOT powerstretch or seal seams
to save time and a kicker will not give the results a powerstretcher will. Almost all carpet manufacturers will not honor a warranty where a carpet has not been powerstretched ,and seams have not been sealed.
Knowledge for the consumer