Well, I'm not sure if you need Hella or KC specifically, but remember, where ever you mount the lights, they are prone to being broken off as well. They will definitely help you out though in terms of lighting. If you're going to spend that much money on lights, I'd suggest you get HID lights, either the pencil beam or flood style depending on what you want them for. It sounds like you're getting 4 lights regardless, at least the ones up high will help the most when off-roading, now the ones on the bumper, those aren't too bad when you're driving on the road, but if you're getting the 130 watt bulbs, then you won't be able to use them on the road.
Something like this.
2x HID off road light spot 4x4 xenon chrome pre-runner | eBay
6000K HID 4x4 Off Road Offroad Driving Fog Lights Lamps | eBay
Or you can buy any foglight you like and buy HID bulbs and ballasts and convert them over for cheaper.
As for non-HID options, they are bright as well and may be all you're looking for. The better the housing, the more light they will reflect correctly. Maybe it's just me, but I wouldn't trust any bulb that only cost $8, seems to cheap to be quality, I may be wrong, but that was just my thinking.