Commercial patterns are often wonderful to work with, but can cost a chunk of the budget for a project if you don't source them properly. I often stalk eBay to be able to find used patterns, or patterns which have been ordered by mistake and are now unwanted. You can occasional find already cut and used patterns, which are often cheaper, on eBay, which saves you the task of cutting out if you can find it pre-cut in the appropriate size! The quality paper is usually really good, making working with the pieces a breeze.
Free patterns are just that, and often you get what you pay for. I've used some brilliant free patterns in the last year, and some terrible ones. They often come without instructions, which means you have to either figure it out for yourself or search the internet for decent instruction. However, if you sort of know what you're doing with a project, free patterns can be a lovely challenge and very useful. I use them often as a teaching aid, as they are reprintable once cut, and an unlimited supply of the same pattern is great! These patterns print from your home printer, so the quality of the pattern paper is whatever paper you print on, and the quality of lines is also down to your printer and its settings.
Essentially, printed free patterns are lovely if it's a small or simple project such as an unlined waistcoat, but if you want to make anything large and elaborate I'd highly recommend using a commercial pattern and making adjustments so it suits your needs.
