Target stores appear to be clearing out the Phantom 3 Standard accessories. I picked up two pairs of props for $3 a pair this week. The backpacks and prop guards are also on clearance.

I did want to ask more experienced owners if there is a recommendation for how frequently to replace the props. I'm still using the first set of props, and they don't appear to have any signs of damage or degradation, but I also realize this isn't something I want to wait to replace until one fractures during flight. Barring smacking the spinning props against something, how many flying hours are safe to expect from a prop?

Thanks.

There's no number of hours associated with prop life that I've ever heard of.  Just inspect them regularly and replace as needed.  

same here, watch for cracks, replace if they contacted ground or something else too hard...  always replace all at once, so they have same usage. I flew on mine for well over 8 months. Replaced when I noticed one to be slightly bent up....