I have a philosophy of NEVER installing software unless I know that I really need it and will use it when installed. Even then, I give it a good 24 hours before I do anything.
The fact that you are hesitating indicates to me that you don't really need these things and the fact that you're asking others to help you justify loading them suggests that you would find them less than useful.
Programs such as those you are asking about have a reputation of not doing as they claim and if they do have a real effect, it is only minor.
Personally, I would steer well clear.
Just my view;-))