I will offer a caution. We had the experience the first week of June in which the kiosks would sometimes not recognize all members of our party as being linked together if we had been riding separately earlier in the day. In those cases the person/people who had become "unlinked" had to be present to book their own FPs.
If you all stay together and ride everything as a group, this shouldn't be an issue, but if you split up, just keep in mind that you may have issues booking the 4th FP for everyone.