I use RTM on the web and on my android phone. I really value receiving reminders through the android app, but got a little annoyed with the fact that I had to receive redundant reminders. In order to receive reminders from the Android app, I had to enable RTM to send reminders via text and/or e-mail as well.

To combat this, I use the "filters" functionality in g-mail so that I don't see those reminders, only the android app reminders. However, this could also be used to bring more attention to your RTM reminders as well.

It is as easy as 1, 2, 3!
1. Set-up your reminders in RTM, using the e-mail address "username+rtm@gmail.com"
2. In your gmail account, go to settings->filters, and create a filter with "to username+rtm@gmail.com" as the search criteria.
3. Set your desired outcomes. If you want your gmail reminders to be low-key, you can set them to automatically archive or delete. If you want to call more attention to your reminders, you can configure the filter to add a special label (like "RTM"), automatically "star" your reminders, or to "Always Mark as Important."

There is a lot of flexibility there, allowing people to customize the reminders that they receive.