I never could understand that "fly like a brick" comment. What I would do is ask them exactly what it means. Have they actually flown the Deb, or are they basing their comments on a plane that they think is similar? Tell them you can't afford a $100 plane, and would they be willing to teach you on the Deb even though it would not be their first choice?

You're trying to get a feel for the depth of their feelings, since you need them more than they need you. Is one of them willing to try something new? Or are they all so set in their ways that nobody is going to help you if you turn up at the field with the Deb? Are you going to get a little ribbing (which is fine), or are they really going to turn their backs on you?