Super-Conundrum

I find myself stuck and I thought I would throw it to the winds of the web to see if any insight comes back. The problem is this:

• I tossed out an idea to let the Apprentices play some of the DC heavy hitters as a one-shot adventure using the DC Adventures/M&M 3 rules
• I don't have anything prepared to challenge the Justice League, just some vague ideas - it was "hey would you guys be interested in doing this" comment, and they took it as "we're playing this tomorrow so start discussing how many Lanterns we can fit into one team"
• I will be running a "Limited Campaign" set in Freedom City later this summer for some of my other players
• I was planning to run a campaign for the Apprentices using M&M 3 set in Emerald City, likely starting with the Emerald City Knights published adventures, giving me the long-sought two-playing-groups-in-the-same-universe situation
• It occurred to me this week that I could run the ECK advenutres and kill two birds with one stone by setting it (and Emerald City as a location) in the DC Universe

So ...

I am not sure whether to take on the challenge of moving Emerald City to the DCU. On the plus side it gives me a reason to use all that nifty DC info I have in it's natural habitat and let's the characters rub elbows with all of those other characters - and possibly lets my players play some of them. I found some discussion of this on the Atomic Think Tank (apparently I am not the first to think of this) and it was helpful. Admittedly though,my DC knowledge is far less than my Marvel knowledge, but hey - that's what the books are for, right?

However, doing this takes them out of the Freedom City universe and costs me that oh-so-awesome setup of having two hero teams on opposite coasts who can hear about each other's exploits, come into conflict, and work together to stop the truly world-wide threats.  

My homebrew superhero universe is staying out of this one. This is really just a decision between published settings for this particular set of campaigns.

So, if anyone has any thoughts on this, please share!