I mostly use three:
 
Kenkyusha's New Collegiate JE Dictionary. This is quite good for general J-E use (it lacks some colloquial expressions and specialized vocabulary, but that's to be expected) and has tons of usage notes, but it's intended for Japanese readers, so no furigana and the notes are, of course, in Japanese. Still, very good, and an OK size for carrying to class.
 
New JE Character Dictionary (Jack Halpern, ed., Kenkyusha). This is my main dictionary for kanji. Halpern and his crew devised a new method for very quick kanji lookup (though you can use the standard ones, too), and it works really well. Also lots of excellent reference material, and some other innovations. Too big to carry around, but good to have on your desk.
 
Harper Collins Shubun Pocket EJ Dictionary. This gives essential E-J equivalents, often with different senses for a given word. All entries give the Japanese word as it's normally written, followed by the pronunciation in romaji. It is small, but I don't think it fits in most pockets. Useful when you need to communicate, but the lack of usage notes for Japanese means that it sometimes lacks precision.
 
I'm not sure how to rate these because I haven't surveyed "the market" in a long time, but they seem OK. Somewhere I have an old Canon Wordtank, but after a while it seemed like I only used it as a quick index to look up the pronunciation of a compound so I could check the paper dictionaries to understand the real meaning. These days I just use the Halpern dictionary for that (it's often faster), though I sometimes carry the WordTank when I travel.