I ride a Litespeed Toccoa (hardtail) that I've had for about four years. It's a great bike, and a real joy to ride. It fits me perfectly, and there is nothing that I would change about it.
My riding buddy has a Seven (also hardtail), and he absolutely loves it, too. I think the big difference is that his frame was custom fabricated to fit him, whereas mine was right off-the-rack.
I honestly don't think you would go wrong with either. Lately, I've also read some pretty nice things about Airborne ti bikes. You might want to check them out as well.
Personally i would go with a Seven so i could get custom specs if i had to choose between those 2 companies. That being said my last Ti bike was a Merlin. But i am wondering why you chose only those 2 companies? There are so many Ti companies out there.. What type of bike are you looking for?