OEM is just an acronym for Original Equipment Manufacturer. A lot of car manufacturers use Bosch (Nippon Denso as well) injectors. If you were using the same size you had now, no, switching brands wouldn't necessarily help. You could pull injectors from a fuelie Corvette and use them though, so long as they were the same style (high current or high voltage) and physical size (not flow size) as your stock ones, and they'd probably flow more. Your best bet is probably to talk to some people who are savvy in high performance fuel injection (speed shops, people who are really into scca, engine builders who build fuelie drag cars, etc.) Ask them which brands or styles they'd suggest.
I'm not trying to dog anyone here on the board, but getting information from a variety of sources helps you get a better idea of the big picture.