Sorry for a late reply.
You can use netbeans as it provides lot of things in the mobility pack.
But I am more comfortable with Eclipse with EclipseME plugin. Also EclipseME which was and individual effort is now being developed as Mobile Tools for Java by the team lead by Motorola, Nokia, RIM and others with official support from eclipse. So its good to bet on EclipseME for future.
also I use eclipse of my other work (non Java ME related), so its better for me to use same IDE instead of jumping between the two.
*eclipseme.org/
*www.eclipse.org/dsdp/mtj/