Depending on where you are, it may be easier to find used DVDs of the ADV release. They are, IIRC, dual versions, with both the dubbed Robotech edit and the original unedited Japanese version with subtitles.So should I bother looking for fansubs of them?
If you can't find those DVDs then the high seas are the only other choice. Given the licensing mess and HG's stubbornness I don't think Southern Cross and Mospeada will be streamed or rereleased officially. Not until the licenses expire.