Pretty good deal but I can see a couple issues with this.
Mainly, the pain involved will vary depending on the person and the size of needle they use. If you have crappy veins, the phlebotomist may

up. They also probably use a big needle (probably 16-18 gauge) and it will hurt. They can't use smaller ones because it won't collect all the different cells.
More on crappy veins, if they find that they can't take it in the inside of your elbow (median cubital vein) or anywhere around there, they are going for your hand. Now this hurts (depending on individual) and to me not worth $60. The vein may blow (damaged) or whatever. So I'd stay away if your veins suck. Best veins are the median cubital and occipital, IMO. Also, if they go for arteries, get ready for some pain. Don't know the difference between veins and arteries? Hopefully the blood guy does.
OP mentioned a saline drip they give you afterwards (seems like they'd take a bit more than a pint). This is just salt water to re hydrate you but to do this they put an IV in you. IVs suck if you aren't in a medical emergency.
It's good money but know all this before going. It's not going to be like stick a needle in you, get the blood, get paid. I can't imagine them letting you leave right away either. I'm sure they would make you stay to monitor you for a couple minutes.
I think the best candidates are people with nice veins so the pain is minimal and the blood draw is fast. Otherwise I'd say not worth the pain and time.
I'd actually be more interested in sperm donation. oh, the shame...