The discomfort level really depends on the area being treated and your personal pain threshold. Most people describe it as feeling like a rubber band snapping against your skin, with some warmth. It's definitely not unbearable though. For sensitive areas like the face or neck, they can apply numbing cream beforehand if you're really concerned about it. As for timing, smaller areas like your neck or underarms take maybe ten to fifteen minutes, while larger areas like your full back could take thirty to sixty minutes. Most places are pretty flexible with scheduling and can work around your availability.