To help you make a visual comparison, we have made a table with samples of each font. The fonts might look a little better if they were installed on your system, but the table gives you the ability to make a quick comparison to decide which fonts might be worth downloading. This table was converted to a bitmap using Paint Shop Pro . If the spacing is good, you don't notice it. Spacing should not draw attention to itself.
Different fonts serve different purposes.
Symbol was really designed for mathematical symbols, not for text. Siniaticus is for graphic artists, and attempts to reconstruct the kinds of letters actually used in older documents, which lacked the breathing marks and accents we find in the fonts we use today. If you display Greek text with an English font, it may look like a lot of garbage. The fonts that look the best also have the weirdest character encodings. Because keyboards are not set up to type these wierd characters, you need to use the macros provided with the fonts.