I have one of those super cheap square ones off Amazon and it's kinda ok, if you get really close. One of the other team members flooded her camera, so I borrowed her baseplate and those futura lights off Amazon for the rest of the week. Wow, what a difference! My footage went from "Ok for surveying" to "use it for promo shots" standard in a day.

Definitely worth the outlay. I bought a pair of them, a baseplate and a couple of arms with the butterfly clips and I'm itching to get back in and try them.