Product review (3 stars): Only slightly better than metal braid, IMHO.
Washing machine hose bursts are a homeowner's nightmare - an unexpected flood that lasts until you notice it, trashing your house.

The basic protective steps are (1) replace your rubber hoses with metal braid hoses, tag those with the installation date, and replace them every five years, and (2) if possible, turn off the water to your washing machine when not in use.

Flood Armour takes that a step father - it has a double hose, with a valve designed to shut the water off if the inner hose bursts.  I'm trying one out, but if I had it to do over, I think I would stick with metal braid.

What's good:  Assuming that this works (and I assume it does), it offers one more level of protection.

What's not so good:  (1) the check valve is pretty big and might not fit in some installations; (2) the unit is pretty expensive; and (3) it STILL needs to be replaced every five years!

My recommendation: take the recommendations seriously and replace your washer hoses every five years; (2) but save some money and use metal braid hoses.  If you're super conscientious, make sure  you turn off your machine's water supply between washes.  If even that's not enough for you, then something like Flood Armour is a good option for a belt and suspenders approach