Mo's is ok. But there are far better restaurants in downtown Baltimore. I would highly reccomend Da Mimmo ($$$), Bertha's(ecletic, great mussels), the Brass Elephant. If its strictly seafood you desire you might try Phillips, The Chart House, or the Rusty Scupper(but these places seem more like tourist traps to me) I also enjoy Sisson's very much ( Maryland's first brewpub. It specializes in Cajun). Drop me a line to let me know what you are looking for and perhaps I could steer you in the right direction.
TrevorBaltimore, MD