I am just a home user & longtime forum volunteer at MBAM forum (different handle).
So, I cannot speak to the security considerations or coding concerns.
I echo @Aura's observations that the move (I cannot call it an "upgrade" with sincerity) has "fixed" many things that were not broken and has likewise broken many, many things that -- by all accounts -- cannot be fixed.
This goes well beyond minor inconveniences and work flow and workarounds.
There are serious functional deficiencies, especially for volunteers, staff and malware helpers who rely on "canned" and BBCode, among other problems.
The new software seems better suited to a dating site than to a computer help forum.
The publisher seems to be "unable" to fix many of large and small regressions and UI/UX issues.
If I were the folks running this forum (which operates much the same as MBAM forum, but at an even higher volume), I would wait as long as possible for IPS to fix what they "can" in a future build before upgrading here.
JMHO and not worth 2 cents,
Edited by MoxieMomma, 20 March 2016 - 05:38 PM.