From what I understand, yes its perm.
As long as you got it now (before said promo end date) for free, it ll stay there.

Hence the "free forever for a limited time"

If I remember correctly it took me almost a month to get to Heavensward, and almost another month to get almost all my crafters to 50 on the PS4, ah damn it, if only my bro hadn't forgotten his PSN Account.

Get the free trial first. You can level every classes to 35 then activate your complete edition. Your character from the free trial will transfer over to the full game

I have played and enjoyed immensely Guild Wars 1 and 2, Eve Online, Astro Empires, and World of Wacraft (first expansion).

I have played and disliked: other Warcraft expansions, Age of Conan, Aion, The Old Republic.

Would I like this MMO?

Funny thing about that, I was on trial before buying the CE of the game, it was too late for me when I found out the days don't stack and I was still on my 2nd day, sigh the disappointment I had when I learned about it.

I actually got back into Final Fantasy XIV last month, hadn't touched it since A Realm Reborn came out, and back then I played for the best part of a year, but stopped subscribing before Heavensward came out. Picked the game back up last month and started a new character on a different world, and my first month is just about to be up (Renews on the 7th), so getting Heavensward for free (I got it yesterday) was actually really nice for me, especially since I'm coming up to the end of the ARR main story quests too, lol.

Honestly, I'd say the only way to find out is to give it a try... they have a free trial available and I'd highly recommend giving it a go!

As for the MMO's you've mentioned, I used to play WoW quite a bit but stopped after Wrath of the Lich King, after that is when I started getting bored with it lol... I REALLY enjoyed the first Guild Wars, I spent so much time on it back in the day, loved farming hydras for dyes and making tons of money too lol, also loved the expansions too! Wasn't a fan of Guild Wars 2 though, bought it day one and after trying to like it for a good 2-3 months, it never gripped me, I took a break (About a year) and went back, but the same thing again, I managed to grind to max level through the world PvP thing, but it just wasn't fun for me whatsoever.

The rest I've either not played or not played enough to give a proper impression.

The atmosphere & music, and the "feel" of a world, because its final fantasy.
Its got the best story line of any MMO on the market, I think.
Other games have a large focus on PVPing at endgame..... "a make what you will of this game yourself", through fighting other players... FF14 isnt that.

The raiding can be quite challengeing (ei. the PVE in this game is the focus, it doesnt just side step that part, and go "our endgame is pvping").
So in that sense its very differnt from Age of Conan, Aion, and Warcraft.

And its probably more like the "first expasion" of World of Warcraft, where focus was probably more on the pve side.

"Would I like this MMO?"

Its the best MMO on the market, so I beleive so, if any MMO is gonna sell you on a MMO, its this game.
Esp if you already have a love for final fantasy.

It has more in common with Guild Wars and WoW than Aion, Old Republic, or Age of Conan. Give it a shot, it's free to try.

Update y'all, good news for NA gamers, the deal is now available you.
SE Store: https://store.na.square-enix-games.com/en_US/ffxiv_heavensward_free
PS Store: https://store.playstation.com/en-us/product/UP0082-CUSA00288_00-FFXIVEX1THEME002