agree on March vs. April. Living here love to ski on tax day weekend (normally when K'stone and Breck close, or close to it). At both places April is warmer and less crowded, BUT my sons and i found the last two years that from 1:30 to closing (4PM) the snow is quite a bit "mushier". Obviously the tradeoff for skiing in a light softshell and long sleeved t shirt. March is far more reliable, and if i recall, better chances of decent dumps still (more unusual in April). If you avoid the spring break weeks, March should not be super crowded, esp. if you have here for a week and do the weekdays skiing. Not sure when they ramp down the tix prices, check their websites. I believe if you hit K'stone and Breck and avoid the Dercum crowds at Keystone by immediately either skiing over to the back mountains or taking the lift over; and at Breck hit Peak 7, T Bar, Peak 9 upper only, or peak 10 you can miss the big crowds on most days.