I have been in both guild (still am in TSM) so here is what I think.
Legion have pretty low requerement so they can't just say the are #1 PvP guild. I mean come on 1,5k rate ?? While TSM have 2k+ still needs it tests. I don't really know why theese guilds are hating each other so much but I don't think there is a big point in that. The main problem with Legion is their leader. He CAN'T lead a guild. Speaking of personal experience. I mean Sprit is just trying to make ppl do his job. He is not online enough, he is not controlling the ppl inside the guild, not watching what they do and if they do it. Never promote, demote. Also he only speaks about changing the guild and new rules etc. but it's all the same. For ex. he tried with some new ppl who just kicked pretty much 1/3 of the guild and nothing changed except the words :X Moreover Sprit is trying to make people farm for him. Ever since I joined Legion he is just talking about some giveaways of moneys, celebrating and stuff but it's all for him (my opinion).
In TSM things are bit different. First of all there is active leader. Jyx is pretty much a lot more online than Sprit and she is also watching the work of the ppl for the guild. I like it when I see that thing. It speaks for the person a lot. It means the person can be a leader. However few guys are active in the guild chat, but that is common problem in most guilds. I mean ye ppl speak but like 20-30 maximum. That's a bit of a problem.
In conclusion I would like to say that there is no such thing as #1 guild PvP/PvE. It is ******ed to make a fight for a game and ruin the fun in it. I preffer TSM now more than Legion because the players are more skilled. Also there is progress in the guild.
Best wishes,
Sucubis