Im not sure if i should get Qarls texture pack 3 or the redimized version? I have a good machine. Which one is more recommended?

What are your pc specs?I have a Intel quad core Q6600 2,4ghz,an ati radeon hd 2600 xt 512mb,3 gb ram ddr2 and I can run the full version smootly

Isnt redimized version better though with hardly any difference?

My specs are core i7 @ 3.2 6GB DDR3 1333 corsair memory, geforce gtx 470 1gb.

Im also looking to run oblivon with texture packs between 50 to 60 fps.

If you intend to keep high frame rates you only have to mind what other texture replacers you are going to install - if any.

A few examples: high resolution ingredient textures and other mods such as high resolution body textures toghether with QTP can hurt performance. Especially if you have a video card with 512MB of VRAM.

Outside the texture replacers, you also have mods that may alter the number of creature / NPC spawn, such as Marts Monster Mod and other overhauls. If you use overhaul mods you should definitely install one by one untill you notice a difference.