I was able to browse plans available to me in Pennsylvania without having to sign up to do so. One of the major complaints was that you had to sign up before you could see the plans; so one of the major complaints has been addressed.

Other complaints were errors and slowness. I didn't encounter either of those.

Of course I didn't attempt to sign up, because I have good employer based coverage, so I can't speak to how well that part is working.

I'm a professional developer and I skimmed over some of the pages' source code and nothing jumped out to me as egregiously bad.

For example they're using jquery-1.8.2 (a javascript library) rather than the latest version, jquery-2. This might seem to indicate sloppiness or a failure to use the latest technology, but in fact it's the correct choice. This is because jquery-2 does not support many older browsers, including Internet Explorer 8. Many people are still using Windows XP and XP does not support any IE versions greater than 8. For those users the website would not have functioned correctly with the latest version of jquery.