I'm struggling to understand the real difference between metal halide and fluorescent.
Attached is a diagram. The top shows the array of the UV beams. The bottom show the beams from a multipoint.
The multipoint will attack the stencil from many more angles then the single point. Therefore undercutting the stencil edges. This causes smaller dots when doing halftones and loss of about anything under 5-10%. This will cause ilregular edges. If you have a multipoint having your exposure times nailed will elimnate undisired results. Great prints can be had with multipoint but better with single point
multipoint at best can expose 5%-95% halftones but most expose 10%-90%. single point can easily obtain 5%-95% and can be 2%-98% with proper exposure
some other diagrams show the single point uv beams all going strait up but IMO thats impossible