Some guys were applied to 777 fleet, while others were looking for a job which gives them the freedom to choose when they work, therefore for them WW contract seemed to be a blessing after flying for decades.
My understanding is that nothing is really guaranteed. In case of 3/2 contract you only get paid the days you work and when you're being positioned. Of course operational needs can overwrite everything. But If anybody out here reading this working for AAI please confirm.
Regarding the bond 500 USD deducted from fees each month and 12K is forgiven if you remain with company for 3 years. Although contract is to be renewed yearly. So basically it is 18K as you said. Other option is deposit upfront of 15K and remaining 8K to be paid over 12 month. Adding up a total of 23K for the TR.
I would suggest to try reaching out for pilots working there to make your decision easier. I believe there are pilots out there for whom this job is a perfect match, and a great opportunity to gain heavy hours and long haul operational experience. Unfortunately they decided to proceed with other candidate(s).