Hi Anon. I am not in the 20-year experience with PD you seek, but only 2 years, but had been on Requip SOLELY, since dx. l/98. At first I was doing great with better movement, improved balance and general overall better energy. BTW I am 67 now. But the side effect of somnolence really became debilitating to my lifestyle. I couldn't leave the house to drive the car for an hour or so after taking each dose. Within the past 6 weeks my neuro approved my coming down from 8 mg/day of Requip and go up on Sinemet CR 25/l00 1/2 tab 3X/day plus one Requip at bedtime. At this writing, I have NO problem with drowsiness, I rarely have dyskenisia, and seem to have enough energy to keep busy with my interests and take care of my spouse. I do hope this helps you in some way. Clare Wilson