I have an Arris WMB760A which has been really great 99% of the time (*holds breath*). It sure beats my former Moto 6151, though I may have had a dud.
Over the years, I purchased a modem or two from Best Buy. Unfortunately, CC regularly decided my modem was supposedly in their inventory every blipping time I had a tech visit and equipment scanned. Hard to dispute if you don't keep a receipt a few years down the road.