sauce pan vs. dutch oven vs. stock pot - any difference besides size?

While all of these are large pots (or may at least come in large sizes) they have different purposes, which lead to differences in typical construction.

• Saucepans are intended for general purpose cookery, and usually have solid construction, and permit searing in the pot, reducing, and a variety of other tasks.

  They are the most difficult to characterize as there is tremendous variation in quality levels and design among the products available.

• Stock pots are purpose built to make large quantities of stock. Since they are not used for searing typically, and liquids circulate via convection making hot spots not a priority, they are typically constructed from thinner metals (steal or aluminum) and don't have good general purpose cooking qualities.

  The main virtues in a stock part are low cost, size, and light weight.

• Dutch ovens (at least real Dutch ovens) are a legacy from the time when cooking was done in hearth or campfire. They are designed to be nestled into the coals or embers, with more coals or embers placed on top of the lid, creating a hot oven like interior--thus the name.

  True quality Dutch ovens will be fairly thick, usually cast iron, possibly enameled, and may have little legs to help nestle it into the fire above the coals; similarly, a the lid may actually fit into the pot, allowing coals to easily be piled on top.

  Dutch overs are actually fairly versatile cooking implements, and can serve for searing, roasting, braising, stewing, biscuit making, soup making, and even some bread applications even in the modern kitchen. Many are large enough to make stock in for home purposes, although they are not absolutely ideal for the task.

You will have to ask yourself, given your own cooking patterns, would the general versatility of a dutch oven, or the size of a stock pot serve you better. None of the sets you linked to has a true dutch oven, however; the one that purports to be a dutch oven has a glass lid! It might be an okay pot, it is not one I would ever choose.

For stainless steel products (without the specialized legs and concave lid to nest coals in), there is very little difference between a dutch oven and a very large sauce pan.

A sauce pan is a small cylindrical cooking pot, specifically made to make finishing sauces to dishes. They will typically take about 500 ml of liquid. You make sauces specific for a dish with them, they generally are too small for batch cooking.

A stock pot is a rather large pot that takes anywhere between 5 - 50 liters of liquid. They are designed to cook stock with as you can imagine, but they have other uses too, I brew my beer in them. A restaurant could very easily use hundreds upon hundreds of liters of stock in a month, you can imagine you would not want to make stock one liter at a time.

A dutch-oven is something different depending on where in the world you are. They are typically associated with outdoor cooking in the new world. In north-america a dutch-oven is a cast iron caserole with a stainless steel handle. In south -africa were I'm from the word dutch-oven is an archaic term for what is more commonly known as a potjie.

The African dutch oven is different in so far as it is a free standing cauldron, also made of cast-iron, and also aimed at outside cooking.