It's a case of "just because you can, doesn't mean you should". If you have something interesting to contribute or their note is about your company and you want to reply, I don't see the harm. But few people will be happy when you suddenly send a sales pitch to their DMs. You can use group profiles or collaborative collections for your VIP clients and ardent fans.
This is where you can share special offers and sneak band data peeks just for them. about something you know they really want. You might also be able to use them in focus groups to get feedback on new ideas or your latest products. You can also create groups for different aspects of your business and use them to help segment your Instagram audience and target your content to them more effectively.
Of course, the more group profiles and collections you set up, the more administrative work you'll have to do and the more time you'll likely have to spend on social media. But if you choose your groups wisely and limit them to those you really need, you should be able to get great feedback, engagement, and tons of data without having to significantly increase your marketing efforts. DNA Spark: From candid stories to group profiles, all you need to know about Instagram's new features These features are so new that it's unclear how useful they will be and how much engagement you'll get.