The Florida Marlins have been hot-dogging it up on the field this year, so far looking every bit like a proud world-championship team. Pro Player Stadium (2269 Dan Marino Blvd., Miami, 305-623-6100), in tandem with Boston Concessions, enters the season with a less impressive record regarding the food served from its countless stands. The same veteran lineup of vendors is back on hand, although Mrs. Fields has vacated, leaving Carvel as the only well-known chain on the premises. Pelican, Sunset, and Seaside Grills continue to dish standard ballpark grub -- chicken wings, chicken nuggets, nachos, pickles-on-a-stick (I kid you not), hamburgers, hot dogs, corn dogs, cheese fries... at the same unpopular prices (hot dogs $4 to $5, sodas starting at $3.50, a 20-ounce beer $5.50). Here are some of the better dining options: The grilled chicken sandwich at Seaside Grill is pretty good; kosher snacks at Old Spadina are better than most and, well, different; High Tides Bar, section 453 by the "H" ramp, offers the widest assortment of draft beers and mixed drinks.