Are Purple mattresses good for couples with a restless sleeper?

Purple mattresses are designed to buckle around specific pressure, meaning one person shouldn't feel another person moving around. Sleepopolis's review tested the mattress by dropping weights from varying heights (to simulate someone moving around in bed) and found a 4 inch dropped produced a small disturbance that quickly disappeared, while drops from 8 and 12 inches created disturbances similar to the average results from other brands tested. Sleep resource Sleep Like the Dead rated Purple's performance when it comes to motion disturbance between a B and a B+, depending on which version of the mattress (i.e Purple Original vs New Purple 3*).

Yes, Purple Mattress does offer motion isolation. You can find additional information about Purple Mattress's motion isolation features on their customer service page here. You can also visit their homepage to see if Purple Mattress has posted additional information on their motion isolation features.
More information available on Purple Mattress' website.

A Purple Mattress is a great option for couples, because of its unique structure. The grid technology that makes up the mattress gives people the support and comfort they need. Air pockets are created under the sleeper so as to create a breathable setting.
Purple is temperature-neutral, so if your partner tends to run hot at night you can still both sleep peacefully. The mattress will provide protection against heat trapping, which is a huge selling point for couples. Thus the non-toxic materials used to make Purple mattresses are better than memory foam, because they do not hold heat.
It is also worth noting that a Purple Mattress does not leave a body indent, so if you are a restless sleeper you will be able to move around comfortable during the night without disturbing your partner. Ultimately, these features make Purple a great choice for couples.