(1) About Visual Tools
Its depends on the visual tool, and the developers.
I've work with some tasks that can be done by programming, but, can be very tedious, and, by using visual tools, people can cut development time shorter.
If you use visual tools in your project, be sure, everything you do, can be done programatically.
O.R.M. code generators are a good example of a visual tool, for something, that can be "coded by hand", but, its helpful to have a visual tool.
(2) About your project
Does, your project going to be visual related, have a visual interface, web, windows ?
You may require a visual tool.
Or, back-end, S.Q.L. programming, web services, COM, Shared Libraries ?
(3) About your developers
Something, that many people forget, and affect this question, its that not all developers are the same.
There are many developers who are very "textual" and "does not play well with visual tools".
There its the opposite, developers which mind or brain, its very "visual" oriented, and have trouble working with pure code.
You may want to check the previous points, to see how does applky to your question, and get to an appropiate answer for your case. Cheers.