I like to use the bent stems with my straight cobs
I tried doing this too, after someone suggested using a bent stem with an MM Morgan for an 'instant bulldog'. I didn't like the results: the pipe hangs at too steep an angle, and I ended up charring the proximal end of the rim. So, I just went back to a straight stem. Others' mileage will vary, of course.
Speaking of mods, the MM Morgan and Eaton are basically nosewarmers. I took off the short stem and put regular stems on them: now they are either elongated billiards or pygmy churchwardens.