I liked Critical Care but I thought Inside Man was one of the worst episodes of the series. They not only returned the ferengi to the cartoon stereotypes of TNG season 1, it didn't make any sense that Voyager was not more skeptical of the shortcut home.
You're right, they should have been more skeptical considering they'd fallen for this kind of trap many times already, and your point about the Ferengi is also valid. I was able to easily overlook these things though because there was so much to enjoy about this one. I think a lot of my fondness for this episode stems from my love for TNG. Seeing one of my favorite guests from TNG now on Voyager (Barclay) and one of the regular cast (Troi) was so exciting!