After since I opened my account last year with Lucent Markbit (lucentmarkbit.org), I can only describe the experience as death by a thousand cuts. No single issue was catastrophic, but the constant stream of small problems, slow responses, and missing features wore me down until I finally left.
Pros: Regular updates|Copy trading available|Clear documentation|Quick verification
Cons: No phone support on weekends|Spreads widen during volatile periods