Ventajas
The best thing for me was the time they took to get me an interview, get me a project (In Sillicon Valley, as an Android Engineer) and securing my TN Visa The process was top notch and they have a team of lawyers that took care of all the process, in less than 3 weeks I was already on-site with my Virtual Labs client Timeliness on payments was great, I always had clear communication with my Virtual Labs manager (This is NOT common contract jobs) and they make sure to have constant communications with the developers Please feel free to reach out if you have questions about the company
Desventajas
The only downside I can see if that I don't see the job listings or the current positions for the company, I was referred and once inside the company I can see that they have many positions ready for interview, it was easier to contact them directly