I would say the H-Sports are one of the most popular and universally appreciated mods. I and other have said they are the best bang for the buck (pound, euro, etc.). I do not think it is much of a stretch to say the H-Sports transform the handling.
As for drive train brace, I am only familiar with the
A.W.E. DTS, I recall someone here installed one. Not sure who it was or the result.

1982 Audi Quattro Coupe
My wife's first car, before we knew how cool a car it really was.
2000 A4 1.8TQMSCC
Strat SS, Forge 007, Samco, S4 Liner, APR Snub, Lolas, etc.
2004 allroad 4.2 Tip, Winter, NAV, Park Assist, etc.
Mods: factory hitch (instructions by gragravar), H-Sports - HARD (thanks to K2audi & arob ;-)
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