I agree for giving it up. I used to drink 2-3 coffee a day and soda every other day. I agree with the observation of others that you don't get highs in the day, but you can get so much work done in your 8 hours day. You can plan your timings better and you would certainly like that part. I found that you wakeup at regular time in the morning and you get enough sleep. Only think that you should drink plenty of water to avoid dehydration.