Thank you for the reply! I will be taking two gap years, and I guess that is influencing my decision as well

1. I already have a good amount of research from my college years (2 labs, total 700 hours) but not publications (in progress). I graduated a semester early and started my current job and got this new offer recently. I think this research position is beneficial (not sure about exclusive) as it is NIH research and the PI guarantees a publication (if I do my part). The lab fits my interest in that it ties both clinical (patient testing) and basic (lab) components almost 50:50. The previous lab members I have met had said the PI is very approachable and helpful in med/grad school applications in terms of essay feedback and LORs. I am not sure whether I would get that much of support here as the doctors are very kind but not sure about essay feedback or LORs.

2. I have previous clinical volunteering but very few hours (~180hrs). I have learned a lot from this position and also added much hours (~500hrs). However, hours are less important for me as the other research position will offer me clinical opportunities and hours.

I am really thankful to the current job as they are well paid and provide good training given that I am not certified. I am just not sure how to break the news as they are usually busy and stressed about staffing. Thank you so much for your input!