Board Thread:Questions and Answers/@comment-26355650-20151201042252/@comment-26091666-20151201100634

Besides, T4 sonar is easily craftable via improvising the respective common sonar equipment and of course with screws wasted.

As if to prove a point my friend cleared E-4 (Hard) with just one T4 sonar on my account. I never did E-3 on hard because:
 * I saw no merits in T4 sonar which is somewhat easily obtainable.
 * I don't have Akitsu Maru nor do I have any sort of inclinations to go out of my way during the event by LSC'ing and hoping she'd fall out. As a subsequent result during my E-4 Roma farming (farming same node as where Prinz drops - on easy of course) I managed to get Akitsu Maru on my 70th or so try.

"German Reppuu" however is another story, that plus you get 2x Skilled pilots makes it all the more worth it.