I had one installed next to my 200 amp box for about $400. This will stop big hits BUT, I do say BUT, some charge will still get through before it trips. It almost never trips even if surge protectors around the house do go (they are more sensitive). However, on a big lightning strike a few years back, the whole house surge tripped and then my PS Audio Quintet fried. That's ok. I lost a $500 PS Audio to save my entire system.
I recommend both whole house and individual units if your home is like mine and gets hit with surges too often.
I recommend both whole house and individual units if your home is like mine and gets hit with surges too often.