I've been experimenting with them for a little over a year.
They do cut the learning curve back quite a bit if you dose properly and memory retention of things you learn while on is still excellent once you come off. I already learn easily, since I have an IQ of 154, but the racetam class of drugs definitely have a noticeable effect for me. I normally take 10 grams of piracetam in the morning on days when I know I'm going to need to be at the top of my mental game. Piracetam has a profound effect on my interpersonal skills as well as raw processing speed. The cool thing is that I did a heavy run of 8 grams dosed twice during the day (once in the morning, once in the evening) and focused heavily on my people skills during that time to see if the improvement would become permanent. It worked. It really shines when you preload for a day prior to needing to do a bunch of research. I like to take 10-15 grams in the morning and again in the evening prior to any time I need to absorb a lot of information in a short period, then take another 10 grams that morning and study your ass off. Sleep on it that night and I promise you, all your dreams will be about what you were studying. The next day, even if you don't dose piracetam that day, recall of the information should be excellent.
I also like aniracetam but it seems to act differently for me than piracetam. Creativity, most especially artistic creativity, is enhanced while on aniractem. If I take 3 grams or so of aniracetam a half hour before I sit down to work on a piece or do some writing, the effects are profound. If I take it close to bed time, I notice a lot more lucid dreaming events than normal. I've always had occasional lucid dreams but they become quite frequent if I take aniracetam before bedtime every night.
Choline is simply to reduce headaches while on piracetam. Presumably, piracetam puts a greater demand on the brain for choline and that is the result of the headaches. I take about a gram of choline for every 2 or 3 grams of piracetam and that typically keeps headaches away. Fish oil is an important one to be taking while on aniracetam also.