Completely agree, and this is one of my favorite numbers. The financial press loves to focus on Earnings (EPS, PE ratio, etc), but in fact there is sufficient scope within generally accepted accounting practices (GAAP) for companies to do a lot of sometimes less-than-completely-honest manipulating of their "Earnings", e.g. by changing depreciation methods, etc. Earnings is just an accounting number, but cash is cash, and there is a lot less scope for manipulating cash flow data.
Focusing on cash flow is a good idea. Even more instructive is what you can find if you start comparing earnings & cash-flow and the various component numbers related to each of them. In addition to making a useful valuation metric, it is also a good way to spot accounting fraud (e.g. Enron). See also Pietroski score item #4: Cash flow from operations > Net Income. Reference https://www.investopedia.com/terms/p/piotroski-score.asp