You really must have 505 plus i lvl, especial if you are a DPS class. DPS makes most bosses in 10 man just /Smile to face. That is the reason that there are no Pugs at all to run ToT. Not because there are no players ( I am from mid pop server). Just because there is missing catch up mechanic to gear an alt to 500 plus ilvl in 2-3 weeks. Also run LFR takes ages ( I am queing as healer) and bad luck just makes you angry. This is whole hate to LFR. LFR in cata was much much much faaaar better ( even HC ppl rolls to LFR items for friends).