Vantaggi
I was on assignment as a Language Engineer through WeLocalize for approx. 2 years (including maternity leave time). As this was contracting work, most of my communication with the company was for administrative purposes, and with anything I needed, the WeLocalize team was always both very nice and efficient in their responses. Such admin issues included for example overtime approval, sick time, maternity leave details and extension and so forth. Compared with other agencies, WeLocalize are able to offer some benefits (though admittedly I did not use them), and even threw us an offsite.
Svantaggi
The work is still contracting, which has its downsides, but this is of course a generalization about the whole field. For the type of work it is, WeLocalize were a very decent and professional company to work through, and the people I interacted with were always kind, informative and efficient.