There are many TYs out there that are TY in name only these days (as in, they function more like prelim medicine programs). And on the flipside, there are prelim medicine programs out there that are more chill than many TYs. You really have to dig into the nitty-gritty and sometimes you'll still not have a good idea of how cush a program is.
You have to read the fine print carefully. There are many programs that advertise a lot of elective time, but what exactly are those electives? A "Cardiology" elective may actually be a cardiac admitting service where you're an intern scut monkey with a rough call schedule that's worse than an ICU month, or it could be a really chill consult service with all weekends off where you work 9am-3pm on most days. Be vary wary of how call works. Find out how routinely you're on jeopardy (the back up call person for sick colleagues) and how often you are going to get pulled on the weekends to cover the wards. Some places have tons of elective time, but you get pulled to cover weekend ICU and ward day or night shifts every weekend or you're on jeopardy so often that you're getting pulled from your electives nonstop.
Also, don't be swayed too heavily by excessive perks. I personally don't care about free food in a crappy cafeteria if I have to be on call every weekend while I'm on elective. Technology perks are nice, but don't let a free tablet blind you either if the program has serious problems. Beware nice locations as well. University of Hawaii's prelim medicine is going to work you like a dog, which is the price you pay for that location. Chicago, NYC, and Cali programs can and will exploit their location to enlist high-quality interns to terrible programs.
Avoid any place that takes pride in treating their prelims or transitional interns "like categoricals". If they're using that language, their priority is clear: they want intern scut monkeys and they don't have a chill program. In a similar vein, it may be a good thing if there isn't a nearby categorical medicine program or if you won't be on the same services as the categorical program. If you are going to be working with hospitalists primarily, the upside is likely shorter hours and less academic BS. If any program prides itself on relying on residents for the bulk of the admitting, then you're going to be over-worked.
So how do you find out if a program is legit cush? Honestly, the interview day and talking to current interns isn't going to yield too much useful information because any program can dress itself up nicely and present yes-man residents who will project a positive image of the program. I know that while I was at my internship, I said lots of nice things about the program even though there were big gaping holes in the cush landscape.
Talk to the alumni from your school from the past couple years. Or the radiology residents at your home institution. It's really hard to find information online about cush TYs because a lot of people play information close to the vest and these programs change so rapidly (several great TYs have shut down in recent years or changed program directors that completely changed the programs). Otherwise, DeucesHigh is right. If there are a bunch of Harvard-grad future-dermies at a program, that's a beacon showing that place to be cush. Expect stiff competition. There are hidden gems all over the country though, you just need to look.
