I guess it depends on what your goal is.  If rotary games are important to you, then you have little choice but to include a rotary joystick.  If you are demanding about the arcade accurate feel during fighting games, you will probably not enjoy using rotaries (depending on the joystick you go with).  I have LS-30's in my 2-player CP and they work find for many games.  I do not like them at all for some games that require hitting the diagonals.  They feel a bit stiff to me.
But, I'm not one for perfect arcade original controls.  I knew that I would be allowed one cabinet in the house, so I chose to use them anyway since it is definitely possible to use them in any game.  I never played that many fighters in the arcade as a kid, so although the LS-30's surely underperform better quality sticks, I'm not the right person to make that call.  I'm happy to be able to play Ikari, so I give the rest a pass on accuracy.
HOWEVER, I did just upgrade the restrictor plates to round from square.  This has made a big improvement to the feel of the stick during fighting games.  Ideally I'll be able to build my own octagonal restrictors at some point.  I haven't had the time yet, but at some point I'm hoping to get them done.  I made a quick and dirty prototype which felt pretty good, so I just need to finalize at some point.