(This review was collected as part of a promotion.) I have had my glass bowl for a couple years and I love it. It's great for all kind of mixing tasks but especially for cakes and breads. Because it's clear it is easy to see to make sure that everything is mixed in; no flour or liquid lying unmixed in the bottom. It is also great for measuring bread rise because you can clearly see when the dough has doubled, with or without the measurement marks on the side. 
BUT it is so easy to break the bowl just securing it into the mixer stand base. The optimism way to secure it brings the spout in such close contact with the back of the stand that the slightest touch can chip or crack the spout. (See pix) I'm so sorry that mine has chipped and cracked just from regular use. I wish this had a better design.