Another important factor to consider is whether you want the glass to have texture or not. Some types of stained-glass panels are smooth on both sides while others have a smooth texture on one side and patterned texture on the other side. Others are textured on both sides.
Ultimately, your decision will depend on your personal preferences and where you intend to install the glass. Stained glass panels with texture on both sides are ideal for more private areas of the home such as bathrooms.