The easy one to remove from the mix is Volition. It is not a mystery shopping company nor a job board. It is simply a forum like this one.
AFAIK, Sassie, Jobslinger and Presto maps are all related.
Sassie is software used to host mystery shopping companies allowing shoppers to register and view individual job boards.
Jobslinger began as an aggregate job board. Most postings were from companies using Sassie. When I started a decade ago there were also postings from non-Sassie companies such as Market Force. Whether that is true now, I don't know. Jobslinger has expanded their services both for paying and non-paying customers. I don't use it often enough to say everything they have to offer or if there is value to the paid version.
Presto maps is another service I don't utilize. My understanding is Presto is also an aggregate, primarily for the Sassie companies, but in app form. I could not tell you if all jobs from each MSC are available in all formats.
Equal rights for others does not mean fewer rights for you. It's not pie.
"I prefer someone who burns the flag and then wraps themselves up in the Constitution over someone who burns the Constitution and then wraps themselves up in the flag." -Molly Ivins
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