[I] Carhartt[/I] and [I]Grundens[/I] are the best when it comes to warm comfortable, sturdy wear that will last a while. Pricey compared with others, but worth it compared to others.
If you plan on getting into "on your knees work", especially on steel decks, making/breaking tows, and engine room gratings... my recommendation is the [I]Carhartt [/I]double knee work pants (about $45) with the extra purchase of the strapless knee pads (about $18-20)! They are great for both home and work!
"The bitterness of poor quality remains long after the sweetness of cheap price is forgotten."