Do you need to use vats alot in fallout 3? In NV you can get criticals wihtout it..

No, VATS isn't absolutely necessary. It all boils down to your playing style. Some prefer to play it as a first person shooter relying on their reflexes while others prefer to use VATS from the role playing stance, relying on their characters' abilities and not their own. I like to mix it up, personally.

Thank for your answer. I ended up putting a couple of points into agility, so i have an option to use vats.

I currently have a sniper, that was lucky enough to get the Deathclaw Schem, from a random encounter early game. I don't normally use VATS, but I'm growing fond of it none the less. It works differently than FONV. In FO3, it's 15% Crit chance instead of 5%, and you only receive 10% normal damage instead of 75%. Death inside of VATS, is more likely in FONV. Like Justin said, it's all about playstyle. I NEVER use it to snipe. But, with the low total crit chance in FO3, being limited to Luck and a perk or two and the lack of crit gear, using a high crit weapon is gold.The Deathclaw Gauntlet is x5. With all the right perks, using VATS or not, it becomes a 1 shot killer to heavy armored foes. As it negates the DR of an enemy.

I like using it for the side effects of it as well. Granted it is cheating, in some people's eyes, none the less very fun. A melee or unarmed char can close the gap of 10 feet or so on a enemy. Even changing elevations, if they are targeted while your character is jumping. It also negates fall damage. An otherwise leap of death, turns into an assassination when the enemy is targeted before you hit the ground.