Daily rewards at current node amount:
(depends on how many nodes are actively mining)
1 node mining 24 hours = 13-15 DNA ($1.30-$1.50 USD) @ 24 hours
Mining is lesser and lesser now, I have to sit and disable my VPS I failed the validation test because some images that were sent to me are incomprehensible but I still have 90% total scores, just lucky that my wife pass the validation, it's ok I already have a good amount of IDENA that I mined two months ago, and I might be buying more if I have the funds.
Apart of bad and very bad flips, there are also some bugs on the client or node.
For example:
on epoch 39 (if my memory serves) I was unable to submit the Long session answers "An error occurred when submitting your answers";
on epoch 42 I got suspended because the Short session flips didn't loaded at all despite the fact that I have a very good internet connection.
Let's hope that this bugs will be fixed with time. As for the bad flips, I don't think is anything we/devs can do to fix it.