In this video, I look at the difference between 17 of the modifiers in my studio. With such a huge selection of modifiers out there, it is often hard to work out what you need. Hopefully, this video helps.
It wasn't that long ago that lighting modifiers were pretty standardized. But thanks to the Chinese market creating a myriad of off-brand items, there is almost a modifier for every day of the month! Knowing which one you need is really challenging, especially, if like me, you have storage and cost issues to take into consideration.
Going through a mix of softboxes, umbrellas, beauty dishes, and reflectors, the main take-home message is that there isn't a great amount of difference between similar modifiers. So, you can often save your money. A better image will far outperform a better or slightly different lighting modifier. That being said, between the main categories, there are clear differences and very distinct applications for the modifiers.
Personally, for portraits, I like the two-meter high softbox for beautiful soft lighting and great skin colors, but everyone has a different opinion on such matters.