Touring friend asked which website for Chicago to use as she does not want to pay for both during the tour.  Any suggestions as to which to use?  Both have very nice websites.

it seems as if more agencies are on MC.  
We are new here, too, and wonder if there are different types of clientele for each site, also.

Reifficult one to answer but

I would use RoomService2000, not a big advocate of it, but it is better than Midnight Chicago from a quality standpoint

I would suggest that your friend use eros but if she wants to stick with one of the two listed RS2K would be the way to go.  In my humble opinon most MC providers are not GFE types.  One cup rush jobs.  but again its just been my experience.

if she is visiting being on RS could be useful to her as she would then ALSO be able to use their verification services to get persons verified(through them) checked in mins.  Makes things really easy, and is the only online service that has a verification service.  I do trust their process and see alot of their members.