I'm also on lithium at 800mg. I've without a doubt noticed an improvement in my mood and so far I'm very glad I've tried it. I didn't want to take lithium personally but I can't deny the improvement its given me.

Side effects suck. Fine tremor and feel a little ill but frankly I feel more balanced now than at any point in the last 15 years.

Glad to hear you are also having success on lithium. From what I'm reading, if it works and you can tolerate the side effects/ levels ect, it REALLY does work.