Is that all you can say? That they have awesome commercials therefore their career is also awesome? Surely you must be more knowledgeable than that.

In any case, the SAF is a bad choice as a career option unless you're totally into the idea of taking up arms and being paid straight out of our tax money without contributing meaningfully to the economy. You will be competing with dirt-cheap NS labour, and that will basically lower your wages as it is cheaper to them to redistribute your work amongst the servicemen rather than you. Even if you get to a rank that has no NS men, they will find it cheaper to redistribute your work amongst lower-ranking NS officers than to pay you competitive market-rate salaries, unless you happen to be the top guy. Basically, that will lower the value of your own labour. Having that constant inflow of cheap NS labour is just like how an influx of low-wage Chinese immigrants can end up depressing wages in industries everywhere here.

You can try and argue that you have special qualities that NS men don't, but that only means that the NS men are somewhat less efficient at it. If you understand economics, you'll realise that no worker can claim total exclusivity in their job. Everything can be given a valuation in the end. Do you think that has stopped immigrant workers from competing from local labour, even though local workers can claim to have "better knowledge" of the local society? And given that NS men earn a lot less, it's so much cheaper for them to hire NS men. And all that, even though MINDEF takes up the largest budget allocation of all the ministries.