"I kind of long for the old days … when we would actually look at earnings and balance sheets and fundamental growth and top-line growth and these sorts of things," the founder and CEO of Farr, Miller & Washington said in an interview with "Closing Bell."
"I wouldn't be too aggressive. … It's a time to be cautious."
Chris Johnson, director of research at JK Investment Group, told "Closing Bell" he'd welcome a pause or a pullback right now amid the growing optimism.
"The last phase of a real long bull market is acceptance and I think that's where we are right now," he said. "The next one to come is optimism. We're not there yet but you need to be cautious right now."
However, while some are urging caution on stocks after their record rally, portfolio manager Neil Hennessy thinks investors should be buying.
"There's no euphoria on the upside, there's no hot buying going in. There's plenty of reasonable valuations out there," he said in an interview with "Closing Bell."
"I think this bull market continues to go and there's plenty of good buys."
Hennessy, chief investment officer and portfolio manager at Hennessy Funds, said if corporations get tax cuts, the market will go even higher.
"But right now their profits are at all-time highs and so are cash flows, so you should be buying it," he said.
Hennessy suggests buyers look for high-quality stocks and businesses that will be there for the long term.