It's your call, if you have the time and enjoy learning about board repair - DIY. If you couldn't care less about learning to fix your pinball machines then get a new board.
I'm a nerd so I like to work on my own boards, although I will say this Whirlwind I just got is giving me a headache trying to sort out the previous operator hacks. Nothing is better than fixing something yourself though. It feels so good when the game doesn't explode after you turn it on.