Yes, in my experience, they work well. I've always asked questions about things I can easily verify, for practice. For example, the position of something, or any question about something I don't know at the moment but can easily verify without divination, just to test my ability to get truthful answers from the pendulum.
Nice username, big Pokemon fan myself.
If you have experimented with divination and found it to be accurate, you likely have developed this ability in past lives. For most people, your own mind getting in the way is a major problem.
To the original poster (and to you, if this is useful or new info):
If you have a good faculty of divination, be it developed or innate, the actual method you use matters quite little, any will get the job done if they are convenient for you.
I recommend Tarot as the best method by far if you aren't naturally good at divination, mostly because of its enormous symbolic complexity and number of associations which can help you learn, take notes, interpret and improve your intuition skills far more than a more straightforward yes/no or question/answer tool.
Besides practice, symbolic understanding, intuition and meditation (better upper Chakras would, for example, improve divination), I recommend Lord Apollo's Ritual in this matter.
Lord Apollo rules, among other Gods, the many arts of witchcraft. Whenever I got into a new practice, I went to Him in Ritual and asked for guidance, and received the right info, reading material, inspiration etc.
Lady Hecate would also likely help, depends on the individual.
Not good at divination myself, so this is as much as I can give.