I worked through Key West Marine on bulk carriers. The crewing manager was polite, positive and well-mannered, and always resolved any issue without problems. I was left with a very positive impression.
I worked with Key West Marine and left because the salaries were not among the highest.
I want to warn all sailors not to get involved with this crewing agency. They are completely unaccountable. They personally pay the crew's salaries, and not the amount specified in the contract. The salaries are very low, and delays and non-payments are regular. You will have to wait at least two to three months to complete your contract.