BLAUfergnugem Muffler, not fit?

[Minven Wang <mwang@stern.nyu.edu>]

Last month, I finally decided to replace the whole muffler of my
troublesome '86 5kcs.  I bought the whole kit of Fonos muffler
from BLUAfergnugem, for $276 plus $24 shipping.  When I send the
kit to a mechanics, he said the front pipe does not fit the mid
muffler tight, there is some lose play at the joint.  He suggested
to get a Meineke front pipe for about $20.

I called Jim at BLAU, and he said he would sent another front
pipe.  Today, the package arrived.  But to my surprice, it contains
a front pipe and a muffler, not made by Fonos, but made by Bosal.

It seems that the Fonos' midmuffler had a female end, so Fonos'
front pipe has a male end (actually, there is no brandname on the 
front pipe, and it looked like it is custom built to fit the Fonos).
But the Bosal's front pipe is female, so it has to fit Bosal's own
midmuffler's male end.  (so much about the gender, hope it doesn't
confuse you :)

When I bought the muffler, Jim said the Fonos is well made.  Compare
with the Bosal's, I find that Fonos seems has more solid material.
(I'm not a material scientist, that's purely subjective judgement) 

My questions for the net wisdom are: 
Sould I use the Fonos' frontpipe/midmuffler, which may has a lose
fit (some welding may also needed), or use the Bosal's, which fits
better, but seem not as good material (the Bosal's midmuffler is 
a little smaller than the Fonos)?  Is there a price difference
between the two mufflers?

As regard to service, the BLAU is OK up to now.  Jim charged another
$150 for the Bosal stuff but promised to refund it when I send back
the unfit parts.

Thanks!

Minven