I would definitely say the Lumosity is worthwhile because of the mental stimulation it provides through training is really effective. I paid for lumosity for one year and played over 1000games. The results I got were quite amazing my bpi went up by 1000 and I noticed a significant improvement in memory/attention after I stopped paying for it. Since it targets all 5 mental areas I could see improvement in those areas too such as speed and flexibility. It boosted my confidence because when I had to remember things and answer questions I would get it right quite often. In terms of attention span I can pay attention for longer periods of time while retaining information from what I learned. Also the results come after training I didn't train too much I just played the games I liked but training will increase brain power since it includes a variety of different games based on your training priorities. All it takes is training to condition your mind. Further, my verbal fluency improved because I played those word games such as word bubbles rising. The games have a great design and really fun to play you, just have to be motivated enough to play the games. All in all its a great site if your willing to commit the time and effort for training. The time is takes to reap the benefits of training is around 15minutes daily.