The Samsung Pro is great, but the non Pro is not. It uses TLC flash memory.
I'd get the Kingston Hyperx 3K for $120 or Corsair Neutron Series GTX for $125.
But under $100, there is no real good choices. Samsung 840 (non pro) is the only one there.
I wouldn't recommend anything under 120/128GB. At this size you can fit OS, all programs, and some games.