Two piece toilets are simple to transport as they come in different pieces.
Disadvantages of one piece toilets.
Size and weight of one piece toilets.
Also calcium and lime may be uneconomical to remove.
Since you are only dealing with a single piece installing a 1 piece toilet is generally easier than its 2 piece counterpart.
Cheaper models of most two piece toilets and even some one piece toilets are designed in such a way their innards are still covered in porcelain but the shape of their trap way is visible.
One piece toilet heavy fewer rough in options more expensive more difficult to ship.
Toilets sweat in summer supply hot water mix is option this may be slightly inefficient due to more water heat cost and often the use of propane for heat.
Starting with price one piece toilets generally tend to be more expensive than two piece.
They are also more bulky and unwieldy than a 2 piece so you may want to consider the amount of space you are working with as well as how many hands you will have helping with the installation.
My water does contain a lot of dissolved lime sediment.
Also one piece toilets are quite heavy which is a disadvantage during shipping.
Advantages and disadvantages of one piece toilets price of one piece toilets.
Even though a one piece toilet comes in a single unit it is not very convenient to ship.