Truly depends on your abilities and aspirations. Just about anyplace on the Internet will give you chords (some correctly, some not) but unless it's in sheet music format, it's rare for any chord-format song sheet to give the reader the timing of the chords. Being familiar with the songs and being able to hear the changes certainly helps when this is the case.
Knowing different chord voicings on guitar or piano is good but most beginning guitarists especially are better starting out with simple open position chords. The sooner they can memorize these basic chords and not have to look at any chord charts, the better.
Reading through the link, there is nothing remarkable or truly advantageous about eChords. But everyone learns differently. If it's a tool that is helpful to you, great. The tricky thing is not letting the tool turn into a crutch, as can often be the case. As you've undoubtedly read in this thread, some folks have found it helpful and others haven't.
Welcome to Guitar Noise, by the way. Do feel free to make the most of all the many lessons you'll find at the main site, not to mention all the advice you're bound to get here on the Forum pages. Looking forward to seeing you around.
In other words it is in the long line of services whose business model has been made moot by the onrush of technology.
I'm also planning on paying to class on e-chords.com. Are classes are still good?