Morningstar

Morningstar built its name on independent fund ratings, the star system that's become shorthand across the industry for whether a mutual fund or ETF has a decent long-term track record. Its newsletter carries that research-first approach into weekly commentary on markets, fund flows, and portfolio strategy.

Because Morningstar doesn't sell the funds it rates, the analysis tends to be blunter about underperformance and fees than content coming from a brokerage or fund company. It's particularly useful for retirement investors trying to evaluate what's actually inside their 401(k) options.