It depends on what look you're going for.
The Ottoman is classier. I can see it transitioning from work to work related functions (i.e., dinners with the boss) to weekend committee meetings and evenings out with the significant other.
Whereas, the Op Art is totally funky. If you work in a creative, artsy occupation, have a unique sense of style (i.e., not just jeans and a tee but pairing it with an unexpected jacket/blazer, bracelets, earrings, rings, hot shoes/boots, etc.) and enjoy concerts, art gallery openings or cocktails with the girls, the Op Art would fit the bill.