You said your power antenna was a Bosh, right? Well, the "H brand"
you speak of is Hirshmann, I believe. Although I don't believe they ever made
antennas for the factory, they make them to fit many Audis.
The antenna on my 5000cs quattro is a Fuba. It has a special short
mast, and a power booster to help it pick up signals--at least I think thats wh
at it does. I don't think mines working right. These are ultimately more comp
lex and harder to find aftermarket brands. So, in that case, I would recommend
the factory antenna (Fuba).
Regarding rear speakers: ADS speakers are great, but you will not be
able to enjoy them fully unless you have an amplifier. They are also very exp
ensive. If your are using the factory radio, then I recommend a cheaper speake
r, such as Infinity, Polk, or Kenwood (which would also fit in the fact locatio
ns w/ the orig. covers) I would go with Blaupunkt, basically because they made
the radio and (I think) some of the speakers in the car. I know the rear spe
akers are made by ITT, and suck. It is good to use "like" components or brands
. If your head unit is Blaupunkt and so are the other speakers, it is probably
best to use Blaupunkt for the rears also. Certian brands work well with eacho
ther, others don't. All I'm saying is that ADS is great if you've upgraded
the whole sterio sysem, but if not, save your money.