Forget Tony's for sushi - it's a hibachi grill that also serves sushi, but sushi is NOT their specialty.
J & Y is MUCH better - selection, freshness, friendliness, and they always give you something for free - the only downside is they have no liquor license (but you can bring your own beer or wine if you wish) and the location looks a little sketchy on the outside (the building used to be a carpet shop and I think a pawn shop long ago) - check
Urban Spoon or
Yelp for the reviews of J & Y if you don't believe me, but it's the best sushi place in MD, bar none.