I much prefer TTW, it brings together the newer aspects of the engine used in FNV and implements them into FO3. Trust me, it's a lot more fun being able to craft thing's in TTW's FO3 than having to loot or spend caps ( rather rare in the Capital Wasteland. ) New California seems fun and it has a pretty interesting story. But it's voice acting puts me off, I just find that vanilla voices keep the immersion much more, non vanilla audio/voices can really only be aiding in immersion if it's done properly and to perfection. TTW also includes a TON more hours of game-play, besides nothing beats taking a Punga plant whilst listening to RADIO NV and running around Point Lookout from mutated hillbillies.