I use these speakers for about a year and for the moment I could not see any problem. I use an amp with "Inter-M 700" and I think it's a good solution TRRS.
In terms of quality I find irrprochable, but if you think you use it for techno night, do not forget a subwoofer, because the SF15 will not go far enough.
The report qualitprix is really right for the JBL ...
I advise them.