Below is a simple work-around I use until they do provide this feature.
1. In the RSMembers! Users tab, select all the rows you want with your mouse (I start just left of #1 and holding down the left-mouse key, select all the content.), then press Ctl+C (or using the mouse right key, select Copy).
2. In an Excel worksheet, select a starting cell (I start at A1) and then paste your selected content from step 1 using Paste Special and then select Text (Unicode Text seems to work as well).
You'll probably want to delete a couple of excess columns, but at least you will get the subscribers names, usernames and their email addresses; their sequence number could be useful.
It's a shame the Users detail information doesn't contain a column for the membership level information. But at least there is a filter that can be used.
Hope this helps.
