Congratulations on your offers! In principle, both universities will allow you to gain a suitable education in the field that you are pursuing, leading to a degree and subsequently a career in the relevant industry.
However, answering your question may require a more in-depth analysis of both programs, allowing you to make a more informed decision regarding which university to attend.
Western Sydney University:
I assume that by biomedical science, you are referring to the Bachelor of Medical Science (Biomedical Science). As far as I'm aware, WSU has a good emphasis on the content (theoretical and practical) of its degrees entailing science, medicine and nursing. This may potentially lead to gaining an education of a higher standard/quality than that offered at ACU, allowing you to further expand your knowledge and skillset, which could subsequently prove to be beneficial in the real world. However, this comes at a higher ATAR requirement, which is something that you may wish to consider.
In terms of experiences, I have a friend who will be commencing his third year of this degree soon. His experience has so far been positive and he looks forward to achieving good results and finally graduating.
Australian Catholic University:
Ease of entry is something that you may wish to consider. For instance, the ATAR requirement for ACU's Bachelor of Biomedical Science is significantly lower than the ATAR required by its WSU counterpart, making it easier to gain admission into this program.
Additionally, ACU offers a 1-year Honours component that can be completed following the completion of its Bachelor of Biomedical Science, resulting in this degree becoming the Bachelor of Biomedical Science (Honours). If further research into your field of study is something that you feel you are interested in, this is something that you may wish to consider.
I hope this helps!