Promotional material definitely makes it sound like a lot more than it ends up being even if you do it regularly. Also keep in mind how it might effect you at work, you will feel tired and drained of energy the day after. I had a roofing job and donated consistently and I almost passed out even with plenty of fluid intake.

Different labs have different reward tiers and time requirements so if you think the extra 100-150 a week won't bother you I'd say go for it.