I think it depends on WHEN in April you go. We went in the last week of April 2004. While we were far from alone, we never felt like the crowds were overwhelming. I'd call it moderate. With a touring plan and intelligent use of fastpass, we never waited longer than 10 minutes for any ride. Granted, b/c my kids were so young, we were not riding many of the "biggies" like space mtn, tower of terror, etc. so I can't speak to the lines for those rides. But I wouldn't hesitate to go again in late April. The weather was beautiful and we only had 1/2 day of rain. Hope this helps.