Microsoft had published a white paper on choosing a development tool for Microsoft Dynamics GP, at the time of GP 2010 release.
Though it’s pretty old, it’s still valid even now to refer to this white paper.
Download it here: Microsoft Dynamics GP 2010 White Paper – Choosing a Development Tool
Soon, we would all be getting ready for Microsoft Dynamics GP 2013 and I am sure, this white paper would still be valid. 🙂