A group of my co-workers and I are planning a vacation to celebrate the end of our grueling year as medical interns. We are looking for an AI (very flexible on location) that is suitable for a group of 15-20 singles in their late 20s. Price range is limited to max $1200 including airfare for a 5 night trip. Most important is cleanliness. Good food and activities outside the resort would be a bonus. Basically I am looking for the best bang for the buck. We are going in late June. It is pretty overwhelming to sort through all the options. Any advice would be greatly appreciated!!!

You could check out some travel agent websites and see what they're offering. Take a look at Apple - www.applevacations.com - for some perspective. Remember that the quoted rates are likely to be per-person double-occupancy for the cheapest rooms at any given place, and might not include some mandatory fees (airport departure tax, etc.)

For this price point, limit yourself to Mexico---either Cancun or the Mayan Riviera. For that kind of money, you're only going to get something rock-bottom, and rock-bottom is alot lower in the DR and some other islands than it is in Mexico, where the dollar is still sort of holding its own.

Like previous poster said, I would do Mexico. Lots of AI around Riviera Maya area that are great!!

this site should offer you plenty of options: http://www.tntvacations.com/tntHome.jsp

another place to look would be: http://www.resortvacationstogo.com/?source=inktomiH
their 90 day ticker shows the best deals, but obviously does not include june travel yet.

or the same site for cruises, which could be an excellent option for your group (floating ai): http://www.vacationstogo.com/index.cfm?source=inktomi/
again the 90 day ticker.

here's one more site to try: http://www.gwvvacations.com/index.do?command=showHome

agree with doug and mamamia that mex is a good choice. lots to go do safely off the resort properties. look at this page: http://www.locogringo.com/
look under trip research at things to see & do.
dom rep has nice ai's on beautiful beaches but most people do not leave the resorts, without a guided tour, for safety reasons.