sushi mon really is one of the best sushi restaurants in town. the lunch/dinner specials are really tasty...but the best bang for your buck is the all you can eat menu. it's the best way to experiment with different rolls and it's such a great deal for sushi. $25 per person for dinner sounds pricey...but when you consider the fact that it's all you can eat sushi/fish, it's actually really inexpensive.
try out the baked green mussels. they're delicious. also, drink some green tea while you're there. it's so good for you! try the seaweed salad too...but if you're not into it, make sure you share it with someone, because you have to eat everything or else you get charged.
the best place to sit is at the sushi bar. the sushi chefs will get you your order right away and you get to watch them prepare everything too.