Unfortunately the standard ... which I hate. I wish you could buy gift cards there or credit that you could apply to orders. But the good thing about flexpay on the pre-order stuff is they set it up that no matter what plan you pick you ar still getting your item shipped when everyone else does if the item is far enough out. Like this hulk for example.
They do have a neat calendar thing there so you can always see what payments you have coming up etc. With the few things I did flex pay on ... I basically set it up so that instead of having items with overlapping months I chose the payment plans so like when one item was totally done the next one started the month after. You can also choose the date it charges so can try to plan that around when you get paychecks etc. ie. if beginning of month is best or middle of month etc.
But in any case, they send automatic emails that say something like "your flexpay payment will be charged in the next 3 days" or the like ... Then if for some reason you miss a payment it will automatically try to recharge the next week on a friday. And last but not least in regards to shipping as that is your final payment .... you normally get like a 3 week notice or on the newsletter like a month ahead it says what items wil be coming in that next month and shipping. On my Thor hammer they got some in early and just emailed and asked if I wanted them to ship nowo and charge me. I didnt do flex on that one so maybe thats why they asked.
ps. I think they may have gotten rid of taxes for those outside of California.