Pabu is fantastic! It is one of the few places in MD/DC/VA where I found chawanmushi (savory egg custard), which was done very well. Is it better than Seki? I think it depends on what you're looking for. One thing that turns me off is how the menu seems to apologize for its more unusual offerings ("Kokoro sake-cured chicken heart 'the best part of the chicken,' " for example.)
I prefer Seki because it feels a lot more homegrown and the menu options seem riskier and more interesting, but I can be convinced otherwise! I'd love to hear what others have to say.
As far as price goes, I'd say they're just about even. Maybe $30-40/person before alcohol.