The manufacturer recommended media will inherently provide better cell culture performance because the media manufactured will be much better and will give a consistent finished product as it would be made using advanced methods and proprietary technology.
Yes, you may find an alternative media by searching the literature, but the performance may not be as satisfactory as that of the manufacturer recommended media.
So, if you are involved in an important project, I would recommend the use of manufacturer recommended media as it would save time and efforts, though being expensive.
My answer will diverge a bit from Malcolm's answer : in my experience, it is not always true that the manufacturer's recommended medium is best to cultivate the cells.
Depending on the sensitivity and "specificity" of your cells (if it is a heavily modified cell line for example), of course the manufacturer's medium that was designed purposedly for the cells should be ideal, but I think if you can find cheaper alternatives in papers, you should try and see if 1) the cell growth is suitable for you 2) the experiments you are doing are working.
Also, with very specific culture medium designed for one precise cell line, you cannot easily switch to an alternative if you have any problem (contamination, shortage, ...).
However, switching to an alternative might require some adjustments, because it often happens that the manufacturer doesn't disclose the exact composition of the medium : you will maybe have to test the adjonction of some supplements (HEPES, Glutamine, glucose, ...) to find the right composition.
So, I agree with Malcolm that it would save time and effort, but "only" in the beginning, and not on the long term.
Hope this helps, and doesn't confuse you to get different answers !