For 30k+ daily visitors 50 pounds from adsense is really bad..
If you ask me, definitely try content locking or something else for few days and see how it will go, for sure you must do better than those 50 pounds now!
If you decide to give content locking a try, the easiest solution is to register yourself at a CPA company like AWM and grab their content locker code and put on your site. That way you will not need to deal with purchasing locking scripts, setting them up, adding offers manually and etc... If things go well with content locking and you wish to expand then go with any of the custom hosted scripts as they give you more power and flexibility