Need Gearing & Stats Advice

[Kaoskat 0]

I have gearing / stats questions. I'm currently raiding 10-man normal primarily as Demo and am at 560 ilvl. You can see my current gear and stats on the Armory:

 

http://us.battle.net/wow/en/character/lothar/Kaoskat/simple

I do have a full 4-piece set, but my helm is flex and my shoulders are LFR, but I do also have normal mode tier chest, legs and gloves. I've been running Ordos weekly and picked up a war forged helm and chest you can see in my profile . I haven't found any great information about how important the 4-piece set is for demo. It seems to me that an extra HoG proccing periodically wouldn't outweigh the better gear overall. But I'm probably wrong. So my main question is: Am I better off reverting to a 4-piece tier set, keeping either the Ordos helm or chest?

Second question, if you'll indulge me. Am I doing my stats wrong? What I'm going for is the 13153 haste breakpoint for the extra doom tick, then mastery with crit as the lowest priority. I've read some sites that say it should be mastery > haste (to a breakpoint) > crit for demo in 5.4 and some go the other way around (notably Ask Mr Robot which says crit > haste AND mastery). So I'm a bit confused. When I tried to reforge / gem / enchant as suggested by Ask Mr Robot's default, I ended up with a ton of crit, but my dps seemed to drop precipitously. Although, to be fair, I didn't give it much of a chance. It just "felt" wrong (like slow casting, etc). 

Any help / insight would be greatly appreciated.

[Zagam 1,982]

I haven't found any great information about how important the 4-piece set is for demo.

This is a direct quote from the Demonology Guide here on the Forums:

 

The 4pc bonus value is, again, dependent on RNG.  With an 8% proc rate, it would also depend on whether or not you cast a Hand of Gul'dan or a Chaos Wave.  Regardless, extra free damage is always nice.  This set bonus explodes in effectiveness if more than 1 target is available.  While the value of this 4pc is dependent on the number of enemies, it should be deemed necessary, contrary to T15.  Prioritize at least 4 of the T16 Tier pieces.

 

For your stat question, you want a lot of Mastery and Haste.  Crit is your least valuable stat.  This, again, can be found in the Demonology guide.

 

Please be sure to read the guides...there are a lot of questions answered in there.