Which indicator is better? Cash-on-Cash or IRR?

[Account Closed]

The formula for cash-on-cash is cash flow divided by total cash invested (aka down payment). To my knowledge, it's primarily a single-annual indicator meaning the cash flow is annualized and only for one year, whereas IRR takes values over several years (5-10 on average in my experience).

I use CoC all the time, rarely ever use IRR because it can be hard to predict income multiple years out but I recently met someone who is religious about NPV & IRR. He just got a finance degree and supposedly those are the most important, but I just haven't found better use of them. So I wanted to get a second opinion. What's your standard of practice? Do you think IRR is more important than Cash-on-Cash? Obviously this is a per-deal basis but it's an interesting question.