Pros
I have been a contract vendor for Psinapse's competitors off and on for several years, and worked two years as their client.
Here's the thing: You know how things tend to go wrong sometimes when you work with a temp agency, and you need to scramble to get someone to engage you, and you're desperately hunting for anyone to help, and you're wasting all that time and energy to fix what ultimately is supposed to be their responsibility? And don't even get me started about actually temping, and trying to make ends meet while you're waiting for a missed paycheck or some critical piece of paperwork that someone forgot to file..
With Psinapse, *They are really engaged, and good at their job.* The process just works, day in and day out. Nothing ever really goes wrong. You have a relationship with them, and all your employees feel appreciated and taken care of.
If you value your time, and you want things done right, the first time, then Psinapse is for you. Same thing if you're a contractor, and you want to actually feel like you're valued and someone is looking out for you.
Kontras
Their prices tend to be a little higher than the competition, which can be difficult to stomach from a cost/value perspective, given that the quality of their hires is basically the same value as everyone else (at least locally, everyone is sourcing from the same pool of talent).