Quarq led the way with affordable crank based power meters and made them much more accessible to the masses. This is why they made such a juicy purchase option for SRAM, one of the biggest makers of cranksets in the world. The quest for the sub $500 power meter was largely vanquished by Stages with their introduction of the single crank arm replacement in multiple models. They were able to enter and largely capture this price point by offering a good power meter at a very attractive price with a dealer support and service network to match. The problem with their business model was (is) that they are dependent upon other manufacturers, namely Shimano, to provide them with crank arms. This has been a real challenge for them during the pandemic and largely keeps complete control of their price point out of their hands.
SRAM has now aggressively entered the sub $500 market with the introduction of their Rival cranksets with integrated Quarq power meters for just $350. Instead of buying just a single crank arm (and chucking your old one), you get a complete crankset which makes it quite a value, especially if you are considering a new crankset, changing crank length, or even new rings. Crank lengths options span from 160-175mm which is broader than most manufacturers, and ring options are 43/30, 46/33, 48/35 in their 2x models, and 40 and 46t in their 1x model. So far it is available in only a single side version, but I have often questioned the value of dual sided measurement for most riders.
With complete control of their raw materials, and a very competitive price point, they are poised to capture a large chunk of the crank based power meter market. With the acquisition of TIME pedals I am sure a similar process is in place for a pedal based SRAM/Quarq/TIME model in the future. For now it is a good time to be in the market for a power meter.