PS2013 - App Read custom field value through Javascript

This question have been asked before:

http://social.msdn.microsoft.com/Forums/officeapps/en-US/161ac082-d715-49b5-a4e9-5a24cfb7fd98/ps2013-custom-field-value-via-javascript?forum=project2010custprog

But there is no official answar and the solution looks more like a hack then the correct solution.

My question is, what is the correct way of reading custom fields through Javascript?

---------------------------------------------------------------------------------------------------------

Is the "projContext.load(projects,'Include(Name, Id, Custom_5a44a4e6-f9ee-e211-bea4-abaed6b08d31)');" solution supported in current and all future versions?

The CSOM   SDK has some examples, but there is nothing for ps.js and i can't figure out how the get_fieldValues should Work. 

Hope someone can help me out, i can't be the first to try and read custom fields.

Thanks