I was at SDCC this year and I was amazed at how many booths had Funko pops, which was about 20-30% of the booths and there was a line for the Funko area, jam packed with people. I over heard people saying they found some rare ones or newly released that were hard to find.
A few years ago someone bought me a Squirtle Funko Pop, since Squirtle is the best, and I opened it and took it out of the box. They proceeded to freak out that I ruined is value by taking it out of the box…
This opinion is only unpopular in the Funko Pop collectors mind.
Brickheadz are pretty cool though, imo. They can be easily customized and are a nice intro to Lego for kids and such.