CX600 or CX600M?

Solution
The case doesn't have many cable management options so a modular power supply(cx 600m) would be a better choice. You could also invest on a better case like corsair 200r
The 600M, the case you've choosen doesn't feature the best cable management, to get a power supply which is partly modular will help a lot with routing and making everything nice and tidy in your build.

I regret not buying a modular or partly modular power supply, when I bought my components, even though I got a Fractal R4 which has some excellent cable management.

Modular power supplies will always be a overall best decision, as it will provide great flexibility, if you want to buy a new case, add more fans etc.