It is quite easy to generate a fancy looking 3D image of your model bathymetry like the one in the attached image using the mybathy.m function and Matlab's various different lighting options.
By using the "bounds" input you can trim down the model thus making it more manageable when zooming, rotating and panning in 3D.
Example:
% create the fvcontrol object (if you are not going to add any other fvg objects then you could just create a figure)
fvcObj = fvgraphics;
% create the axes into which to plot your bathymetry.
ax = axes;
% use the DataAspectRatio property to scale the elevations with respect to the x-y plane.
set(ax,'DataAspectRatio',[1 1 0.1])
% set(ax,'DataAspectRatio',[1 1 10000]) % Something more like this will be required when your model is in spherical coordinates
% plot the bathymetry within the rectangle defined by 4 points
h = mybathy(ax,'mymodel.nc','bounds',[x1 y1; x2 y2; x3 y3; x4 y4]);
% manually adjust the view angle using the pan, zoom and rotate 3D icons in the figure tool bar
% apply some lighting (see matlab help doc)
lighting phong
camlight right