Trying out the other DAWs requires time too.

It is debatable which is more likely to waste time/effort. I've tried a lot of DAWs, personal preferences play a large part here, along with needs.

I think the point in suggesting "trying" Realband first, is that many users don't know they have such a tool already. Kinda like having an attachment that makes a tool you already own do so much more.

Many users find their ultimate path is to end up in Sonar, Reaper, whatever. But many have also learned that inserting RB into that chain can be quite beneficial. And since RB does a lot of what other DAWs do, you may or may not need the other DAW.

For those who haven't worked in another DAW (and even those who have other DAWs available) if you really learn how to use RB you may be surprised how far it can take you.
This advice isn't aimed at those who already like Reaper, Sonar or whatever, but more at the users who have never even tried RB. If you are comfortable in something else; cool.

Like JJJ said; different strokes for different folks.
But if you haven't tried something you already own, you may be wasting time/money/effort.

Make your sound your own!
.. I do not work here, but the benefits are still awesome