I have an ATPL from down under and an ATP. The checkrides are the same. The difference is the BS and red tape in getting the CAA writtens and medical completed. The written exams I had required a lot more studying than the US writtens...but I will add a lot of the material was totally useless garbage (one question was on how to tune a loop ADF antenna and another was computing an ETP with a wind change using an E6B for a C172 flight plan).
The only other thing I will add I have never gotten a job because of my CAA licenses, but my FAA certificate has been welcomed world wide. A recruiter for an airline in Korea told me the FAA certificate with experience is looked for, because there aren't many places to get experience the same as flying into KLAX,KORD, KJFK, KATL when they are busy with bad weather. Flying around YSSY and YMML on a busy day is like KPIT.
Yeah, but to get that job flying around YSSY you need to pass the local ATPL subjects. I interviewed somewhere just the other week and they basically laughed at the US ATP exam compared to the local 7 exams.