1) Hours depend on the rotation, but in the first year, they are pretty good, since we don't take call. Generally 7.30 to 5 pm. A few rotations start at 8 ish. Some of them are easier than others. MSK, Peds and Nuclear Medicine (each 1 month) are easy and you can sometimes finish between 4 to 5. Generally these months are important to use to study. Other rotations, like IR, are draining. 6.30 to 6 ot even 7+.
Most week-ends are free. I think I have worked 6 Saturday mornings, plus 4 full week-ends on IR. IR week-ends are mainly paperwork days (consenting patients and helping the IR and body department with procedures). That said, the IR crew here is really awesome, so overall I had an excellent rotation.
2) Other co-residents are very nice. Because of the structure though, it is hard to say that we really work together with the upper levels. In fact I don't see most of them on a regular basis. You will see quite a fair amount of other first years when you are a first year, and I have to say that we do have a very cool class. We have to cover a bunch of hospitals, so we are spread out. We have lectures every Tuesdays , as well as most days at noon, and we get together during that time mainly. And you learn to know them as you go. But all of them have been really nice to me. All friendly and helpful. Even when you screw up, they are really helpful to stir you in the right direction right away. I m very pleased with the environment overall.
3) Moonlighting. I would say based on what I am hearing, that opportunities are comparatively better than most of other places. You kind of have to know what services are better suited to moonlight, but in general, yes, you can do quite a bit, particularly as you advance. You can moonlight more or less depending on your needs. As you long are you are discreet, and that it doesn't impact your work (i.e. leaving too early etc...), then you can increase your income substantially, and more so as you advance through training. Second year though may be a bit difficult since we have to take call.
4) Nights. I don't have all details for this. However during second year we have 3 months of nights. Each month = 14 nights (I think these are 10 hr shifts during the week, and 12 hr shifts during the week-end). During the remaining 14 days you have to do 6 shifts 5-10pm. These can be heavy though. Of course this keeps changing. I also think you have another set of 3 or 4 months during residency but that I am not sure. On top of this, you have some week-ends to work (an these are quite numerous during second year). The reason is that we try to offload the third years during the end of the academic year to let them study. All in all, you will have 6 months that are ****ty during the end of second year/beginning of third year. But for having done medicine (IM) as prelim, I think it still better than that.