Here's the thing you need to know about my writing process. I spend years mulling over my stories. Characters live in my head for years. Years. Lysandra first came into my brain in 1988. My next story world I am working has been in my head for 20 years. To start a story with absolutely no ideas of any kind was terrifyig.
Day after day as I pushed myself to get those 1667 words down and somehow people sprang from the page along with locations and situations just appearing from the depths of my being. It was hard and exhilerating. Some days I was was just exhausted and other days I was sentence dynamo.
I've won NaNo three times. And I can say that once you hit 30k, you feel invincible. After that, another 20k feels like a breeze. I like partcipating in NaNo every year to help push myself to get a lot done. It helps to get my writing habit back on track. And it is fun meeting with other writers. I never regret talking to other writers.
My favorite part about NaNo is that even if you don't "win", you still do. You may not reach 50k words but you will have a whole lot of new material and that is the most important part. You have something on the page if you are ever going to be a writer.
If you are trying to decide if you should do it or not, I say go for it! NaNo is not for everyone, but I think everyone can benefit from pushing themselves to the brink like that, at least once. You will be surprised at what comes out of you.