Its nice phone for heavy use, but after updates I am feeling some lag in phone. After deleting some catche and unnecessary files and clearing huge whatsapp groups chats. It is now showing some improvement. Overall a good and handi phone. It has nice grip in hand, quite impressive display as well.
Yes that will backed up in Google Drive, but i recommend you to back up your data separately instead through whatsapp back up, because if you delete something from chat that will also be deleted from whatsapp backup, however if you opted to not delete from device media than it will remain on your device internal storage.