Good question, Sasha. I would say "We have always listened to our clients and (we've) acted on their...." In my opinion, both phrases should be in the present perfect simple. Of course, the choice is up to what the writer is trying to communicate -- if there were only one option, there'd be no point in using different verb aspects. The reason for the present perfect *simple* is that the company has listened on various occasions in the past, and taken action in the past. This is especially clear as written, where the second phrase is in the simple past ("we acted"), although personally, I would use the past perfect (simple) in both phrases, because both phrases refer to actions *completed* in the past, for which the exact timing in unimportant, but which explain the present fact that the company is successful today. Remember the questions: "So why do you think your company has been so successful?" If the question were, "So why do you think your company has been having so much success lately?" You might say, "Well, we've been listening to our clients...." Note that it would be rather strange to use the present perfect continuous with "always," because the present perfect continuous emphasizes the present continuation of the action or consequences of the action, whereas "always" emphasizes the start of the action a long time ago.

You should use the present perfect continuous only when something is temporary, and/or is happening right now. Think about the difference between, "I have met Queen Elizabeth" and "I have been meeting Queen Elizabeth"! For the company to say that they "have been listening" and "have been acting" implies that they won't continue to do this in the future.