What Format is Best for Coloring Pages?

I am working on adding additional free coloring pages to my Surfnetkids site, and wondered what you thought was the best format: Adobe PDF or HTML. Let me explain the pros and cons.

Adobe PDF provides great print quality, and will always print out a full coloring sheet (i.e. not just a small image surrounded by a lot of white space.) However, the PDF files are a little bigger than HTML pages, and therefore are slower to download if you are on a dial-up connection. And they do require you to download the free Acrobat reader program.

HTML pages are fast to download, but they do not provide great print quality. Unless you know how to set your print settings, you will get extraneous URLs and other stuff on your printouts. They don’t always print a full page (small image, lots of white space) and sometimes a single coloring page will even print out over two pages instead of one.

What do you think? PDF or HTML for printable, coloring pages?