SupportYourApp is good, but your overall experience will depend on the client you will work with.
Pros
SUP was my very first professional experience, and I appreciate them for giving a chance to a newbie with no prior experience, it meant a lot to me. After a relatively short period with them, I was promoted, a decision that was made solely based on my great performance. This was something I appreciated about the company. Growth opportunities are available for anyone who is doing great work, despite their background and where they are coming from.
Cons
As mentioned, SUP, as an administration, HR, etc., are good and friendly people, but your overall experience will depend on the client you work with. If the client is not very nice, then your experience won't be very nice. - The salary, I am not sure what criteria they rely on to pick the salaries of independent contractors, but I was once shocked to know that a new hire agent is making more than me with +2 years in the company, and even after being promoted. I requested a compensation review for the first team after 2 years, and I was granted a minor rise, but even with that, the new hire agent was still making more than me, the senior who is literally training him (me). The promotion came with a significant rise in responsibilities, but not much in salary. There are lots and lots of other cons I could mention, but they are all related to the client, and since this is a review for SUP and not the client, it's not fair to put them on SUP. The con of SUP in that is, I would say, is sometimes saying Yes to anything coming from the client. Sometimes they allow the client to set some expectations on the team that are not healthy or reasonable.