Im about to buy TES V: Skyrim - Legendary Edition and Dishonored GOTY. Any reason not to buy them?

Well, you should have bought at summer sale :\
If I were you, I'd try to find gift copies of them on steamtrades. People bought the summer sale -75%, -66% ones, probably you could make a better deal than just buying the full price from steam.

Nope, but you should had bought them in summer sale when they were cheap or in winter sale if you can wait.

I didn't play to much since i have others games but they are great especially TES. I suggest to go here http://www.nexusmods.com/skyrim/
You have allot of mods that will improve your game and give you tons of hours full of fun.

Yes. Combat is so simple in Skyrim. You don't have any control on the swings like Dark Souls, let alone any complicated planning and analyzing your enemy.

I was an Elder Scrolls fan at first, but after playing the Souls series, I just hate playing ES series anymore. The spells are numerous and you can mod the combat but still.

Dishonored is good till the very end. The last mission made me hate myself for wasting my time on it.

Case closed i bought them. :D :D

"Any reason not to buy it"

They are crappy games. Skyrim doesn't even offer ANY kind of challenge, as there is level scalling (so the game makes sure you always win when mashing buttons at random) and Dishonored is a mediocre action game (and stealth in that game sucks and is pointless).

I'm not going to elaborate more as these games are not even worth to be talked about.