I also have the same weight goal. Here's my suggestions:
Depending on your current diet, you may want to use some time to clean up your eating habits BEFORE doing the cleanse. Especially if you use caffeine and/or refined sugar. These can create intense "cleansing reactions" and withdrawal symptoms over the first few days of your cleanse. My first Master-Cleanse was horrible for almost a week because of the carb/sugar withdrawal.
If you have a pretty clean diet already, then you may want to try cleansing now. See how it works for you. I drop about 2 pounds/day for the first 5 days, then slow down to 3-5 pounds/week.
I also did 2 5-day juice fasts and got a lot of benefit from them. Weight loss was a little less, but I had more energy and felt better than the beginning of my MC's.
So examine your personal situation, and let us know what you decide. You have a wonderful journey ahead of you, and fellow travelers to share the challenges and rewards with!