the OM 4-way has 4 usually 1 inch outlets. You can insert I think 3 different "drums" into the unit that allow you to change the frequency of how often water is pushed out one of the 4 openings. You will also need to check OM website because the OM is only rated for around 3,000 gph or so ( perhaps more depending on which drum you get).
The wavysea or other option of Sea-swirls just rotate the water back and forth with their sweep motion and usually you have steady stream of water coming out of them. You could add a squid, but they are not rated for much flow - least don't think they can take full flow of dart or more.
I run my return through two 3/4 sea-swirls. On separate system, I have closed loop with dart pump and OM 4-way. In addition, I have two tunze stream 6100's.
There is adding toys, and then there is adding toys. What is your goal here - more flow in tank? What are you currently using for flow?
When it comes down to ease of adding flow, hard to beat the ease of adding a couple tunze streams on a 7095 controller. Sure they are a big bigger to look at than small inlet/outlet of closed loop pipes, but you can spend as much or more adding closed loop with dart, OM 4-way and pvc pipe and fittings.