not to burst your bubble but i was checking out forums last night and while 3.3.5 is coming out this week on US servers, Ruby Sanctum will not be open until 3.3.5 is on all the servers world wide. so about another week or 2.
but in the mean time that gives people plenty of time to research the fight.
and seriously, "it just came out" is not a valid excuse for going into a new raid clueless. I've done this raid on the PTR and you will wipe all night if people don't know what they are doing.
phase 1 is easy, but phase 2 was the pug stopper on the PTR. also much like OS, the minibosses save you to the raid, so whatever 10/25 people you start with, your stuck with them and there is no wipe a few time,s disband and join another group like people did with onyxia.
regarding difficulty and the kind of gear you can go in with: onyxia was a raid to prep you for toc, but this is a raid not to prep you for icc, but H icc (loot/difficulty wise). meaning just plain heroic farming gear is not necessarily enough.
strategy guide links and videos are on this link below
https://thecircleguild.forumotion.net/raids-f17/the-ruby-sanctum-t88.htm