Engine dwell question

Here's an interesting one.
I have twin 4.3 liter, V6, 1989, OMC King cobra I/O's. I just recently 
replaced the ignition points with an electronic module deal I got 
through NAPA. The first conversion went fine, the resulting dwell angle 
is 30 degrees. The engine manual recommends a dwell of 38-42. The dwell 
is not adjustable with the kits. The second one did not go well as the 
part that went on the distributor shaft was missing some magnets and the 
kit had to be returned. It took months to get a replacement kit and the 
new one has a completely different appearance to it. I did the 
conversion and the dwell on this engine is 44 degrees. The timing and 
idle on both engines have been adjusted to spec.
Both engines seem to run fine, but is the dwell of the first one too far 
off what the spec should be? At what point is the spark going to be 
seriously weakened as a result of the dwell angle? Should I insist on an 
exchange of the first kit?
Any thoughts?
Regards,
Kevin