I recieved 5capsules as a sample from the Nutraplanet order I had.
I weight 180lbs which should theoretically have put me at 4 capsules. I wound up taking all 5 capsules as I figured having 1 extra (if I took 4) would be useless.
RPM gave me a clean stim feeling while I was in the gym. I was actually very tired the day I took it and part of the reason why I use a lot of stims is I workout approx. 9:00pm-10:30pm which is always in the evening after 8 hrs of work.
I never had any sides from RPM @ 5 capsules, and it took about 25 min to really feel the full effect of it.
I would compare 5 RPM caps to 1 R4W caps. I know how 1 R4W feels and I know how 2 R4W feels. The 5 RPM caps feels close to 1 R4W caps. I only take 1 R4W cap b/c 2 will keep me up all night and I need just something barely enough to take care of my evening workout.
R4W is more aggressive and for ppl who read my review before I had some side from it. I can really feel when it hits. RPM is much more mild and subtle even @ 5 caps.
I could be completely ok to go to bed @ 5 caps on RPM and it is very friendly.
I am basing this off of one sample of RPM so take it for what it is worth.