I also like National Quilter's Circle (annual subscription -- first year is $9.99; subsequent years are $39.99). Sometimes I've also signed up for a month at a time with CreativeBug -- they do not have many quilting classes but the ones they have are good. CreativeBug (
https://www.creativebug.com/) is more project focused and, like Craftsy, they have a lot of classes that aren't related to quilting. NQC is more skill-building classes and some of their videos are just a few minutes long (others are up to 4 hours). There are some basic classes on NQC that you can watch for free through YouTube. Then, they have their Premium Membership where you get access to many more instructional videos, receive 2 downloadable videos & get some kind of a discount on DVD sets & the small selection of quilting supplies they sell. The most exclusive membership is their Gold Membership. I just got a nearly-free trial of that & must say it is outright amazing. I get all the stuff from the Premium Membership, plus 4 exclusive online video courses, 4 downloadable full-length video courses, and 4 downloadable tutorials in PDF format; in addition, I can email their team of instructors any question about any of the many dozens of techniques they teach & they will prepare a personal response for me. Honestly, it is my favorite site of all. I have learned so much about color theory, free motion designs, choosing fabric/batting/threads/needles, precision cutting & piecing, art quilts, etc, etc, etc. I almost feel like if it isn't on NQC, it probably isn't quilting.
(
http://www.nationalquilterscircle.com/)
I've taken classes on both Craftsy & iQuilt. In general, I've found the iQuilt classes are higher quality classes. iQuilt classes are more geared toward confident beginner/intermediate quilters and would even be appropriate for professional quilters looking to improve their skills. Many of the Craftsy classes I've seen are more focused on shortcuts to success and having fun. There definitely are exceptions to that (Jinny Beyer's Craftsy class is all about intricacy & excellence; Joanie Zeier Poole's iQuilt basically just explained how to fold paper & left me wholly unimpressed), but as a rule I've found the iQuilt classes more advanced and more focused on producing amazing, award-winning quilts and Craftsy classes have been more helpful to me if I really didn't have the first clue how to do something (e.g., make an Irish Chain quilt from start to finish). There is space in the market for both of them & I've personally benefited from them both, but I do have a slight preference at this point in my quilting career for the iQuilt offerings. When I get those iQuilt coupons for $19.99, I snap them right up because AQS members get another 20% off that price (meaning I only pay $15.99).
Both sites offer helpful downloads. iQuilt also links to resources in the AQS store like books/ebooks by the instructor. Both sell the fabric and/or kits needed to make the projects, but Craftsy usually has better prices on fabrics/kits than AQS and they seem to be of comparable quality. Unlike Craftsy, iQuilt members do not have a questions tab where they can communicate with other crafters/quilters. If you watch the entire class & still have a question about something that isn't in the FAQ, you can contact the instructor directly through the platform. I did that once & was so thrilled to get a personal response back from instructor Cindy Seitz-Krug! I felt like a VIP.
I'm sure that's way more information that you wanted. I take a lot of online classes because my disability makes it difficult for me to attend live workshops. Fortunately, we live in a time where there are tons of high quality classes online & even if the video isn't perfect, I can always watch it over & over again until I have figured out what I'm supposed to do! Neither iQuilt nor Craftsy, to my knowledge, allow users to download videos but they are formatted in a way that I can easily watch them on my smart phone & have it right there next to my machine to refer to while sewing. I really can't recommend these platforms highly enough. They are all so wonderful that it's hard to choose just one. That's why I'm glad for NQC -- I can get my weekly fix of online quilting classes without having to pay another $15-30 every time -- but I guess that makes me a quilting-video junkie. haha