Shares of energy firm Valero Energy Corp (NYSE:VLO) are 0.9% lower before the opening bell following a bear note. Piper Sandler, who also downgraded several other oil sector names due to capacity and demand worries, downgraded VLO to "neutral" from "overweight" and reduced its price target to $123 from$169.In its note, the analyst still called Valero Energy stock "best in class," but said there's "less room for outperformance." Watch out for other covering brokerages to follow suit, as 14 still rate VLO a ...