Ok, Trsempower.com is a company called Total Research Solutions or 'TRS'. I have been signed up with them for some time but have never chosen to do jobs for them because the jobs I have seen are signing up with on-line companies for a month. They do pay a little bit and they do reimburse for the trial period, but it is up to you to go through the hassle of cancelling the service so you do not continue to rack up charges to your credit card each month. I have heard no complaints about folks not getting paid but a fair number of complaints about the time and follow up required to cancel the services.
maretforce.com does not bring anything up on my screen, so I will assume you mean marketforce.com. These guys are a major player in mystery shopping these days as they have bought out other companies. Their 'family of companies' now includes:
Speedmark - many of the old jobs from Speedmark are now appearing through the Shop 'n Chek entity which was also purchased by marketforce.com and some of the remaining shops are still on the old Speedmark website which has been bought by CustomerImpact
Certified Marketing Services/Certified Reports - jobs from these two are still being done on their old websites as far as I can determine
Shop 'n Chek - jobs from this company continue to be done from their old website plus they have jobs moved over from Speedmark and jobs from SG Marketing which are offered at about half the price they were with SG Marketing.
SG Marketing - used to have some fairly decent, well thought out bank shops. The jobs have been posting on the Shop 'n Check boards this year.
I believe you still need to sign up for the different 'branches' separately, though I don't believe anything is available at all through SG Marketing (Level Above) anymore at all and your other two choices are Shop 'n Chek and the Certified group.