Pay extra/invest the extra?

[Mark K.]

I've listened and watched a lot of podcasts and webinars and I've read a few BP books so far. I'm still learning a lot. 

I've heard @Brandon Turner talk a lot about investing any positive cash flow to buy more properties. I know I've heard him mention that some folks like to pay extra on their mortgages, but he prefers to invest to buy more properties. 

I'm currently reading @David Greene great book on Long Distance Real Estate Investing.  In it, he mentions the benefits to paying extra on the mortgages to pay them off quicker. 

I sort of like the idea of paying a small amount extra on each mortgage, such as $25-50 or so. But, I'm also tempted to put much more towards one of them in hopes of paying it off a lot earlier. 

The other side of me says to save all extra funds by not paying extra and to accumulate more cash so I can buy another property. 

Is there any advice from all of you here about the best way to do things?