Don’t know (or really care. I’m sure people still view as backdoor, but for all intensive purposes, the caliber of students in strikingly similar if not virtually the same. So those perceptions are merely elitist and not based in much fact. By asking about them being stigmatized you are basically asking redundant questions like about the academics. However, many wouldn’t be able to tell the difference and Oxford students are extremely well-represented in clubs, student government, and even well-connected to administrative apparatuses it seems. Seems that focus on leadership at Oxford pays off) about the others, so will end up only mentioning them in passing:
Can only generalize on the academics.
In many areas (especially outside of STEM), the beginning level course work wlll be tougher, but that just makes sense. it is smaller. Smaller schools that are remotely selective will likely give a higher graded workload in courses. Colleges courses are generally run based upon efficiency. So at a large R-1 where course sections are much larger, instructors (especially all the research faculty) are generally (if they teach a large course) going to settle for lower level tasks and a lower workload to make grading easier.
Pre-med is basically the same everywhere. Do you mean the science courses? That is an integral part of the experience of those pursuing the pre-med track, but it is not synonymous. I would say the lower division courses except for chemistry may be run better at Oxford and the labs across virtually all of the required STEM disciplines are certainly run better/more interesting. There is a reason why top and even the most random LACs no one has even heard of do well at producing future scientists. They are immensely helped by size.
In general, you could find the same rigor on main as Oxford, but since it is much larger and there are many more courses, it is of course less consistently rigorous. And as I said, the research mission of the university naturally interferes (though they are working on making it congruent with) undergraduate teaching. Are you looking to avoid rigor or something? Why does it matter? Your goal should be able to get a rich experience in those science courses (and others) and often that entails getting a mixture of some of the best and more rigorous teaching. If you can seek that out and do well/solidly, you will get an amazing experience and probably better rec. letters. Believe it or not, many instructors who give out a lot of As for low standards tend to write more lukewarm letters unless a student truly stood out even among the sea of As. Both schools are/can be quite challenging, but are not stifling, so don’t worry how the rigor of either will clash with your pre-med goals. If you do the work and stay intellectually engaged, you should remain competitive if that is really what you want to do. These are not engineering schools or anything like that.
And stop worrying about prestige and “stigmatization” so much. Worry about the learning and social environment. It will of course be different from a large research U (Emory has a scaled back party scene, so imagine a smaller school? Really imagine most schools that are LACs with with high achieving student bodies. There will be some parties and events, but most even well-known LACs are located in somewhat isolated places much like Oxford in hopes that the school could be more academically and “life of the mind focused”. Oxford faces having the double-edged sword being directly associated with Emory University which means that the desire to create an environment similar to well-known LACs often clashes with the attitudes of tons of pre-professional, especially pre-business and pre-meds that the Emory association attracts).
Either way, if you think a higher workload/requirements for more academic engagement and a more scaled back party scene is not for you, I would basically avoid most remotely selective LACs and hedge your bets with research universities. There should be no looking for a relatively “easy” LAC that has strong students. They don’t really exist and most who attended didn’t go in particularly concerned about that aspect. They went in more so anticipating and maybe even desiring it. If you are a more stereotypical pre-med that just needs high grades, some relevant ECs, all while maintaining an ultra vibrant social life, most LACs may not be a fit unless you consider more quirky (imagine American college movies and the hierarchy portrayed. Usually those at these LACs are not your Greeks are Animal House types in droves. They are often more like the studious, artistic, “nerdy”, and quirky folks that are barely portrayed as part of the undergraduate experience in the media) and scaled back social scenes acceptable.