The eyeshadows are not very pigmented; I find them to be too sheer, especially w/ the lighter ones. The darker ones are more pigmented though and work well for supplementing other colors. I have the Cameo Glo blush and I think it's really pretty, personally. It also shows up well and I'm NC40. Basically, their products are just not very consistent.
I do love the fact that Mark makeup is unique in a lot of senses and I love their customizable compacts, but the quality is not amazing. I guess you get what you pay for though, since it's pretty affordable.
As for the reps, it is very difficult to make much profit. You have to have a large network of friends/coworkers/relatives willing to purchase their products. It is difficult to sell Avon, and in my opinion especially Mark. Also, the percentage you earn from products is not the best. I believe you earn about $25-$40 for every $100 sold, which is not too bad but it is difficult to sell $100 worth of Mark products all the time.
Overall, I do recommend trying some of their products such as the blushes, darker eyeshadows and if I can remember, the concealer is not too bad either. Good luck!