OKbowhunter,
I have built quite a few custom 4" stabilizers,I have considered putting a 4" on my site as a standard option.
The only problem with a 4" for use as a rear mount stabilizer is that on several brands of bows....a 4" is a little bit to long to allow for enough clearance for the buss cable to move forward when the bow is fired!
I have a Mathews Q2XL and have a 3 1/2" Stealth mounted in the rear stabilizer bushing,a 4" is a tad to long for most Mathews!
I have shot the bow with a 4" mounted on the rear and noticed the cable moved far enough forward that it came incontact with the rear mounted stabilizer,this is not a problem on BowTech or Darton,Hoyt has no provision for a rear mounted stabilizer that I know of.
Although the cable did not show any sign of abrasion from this slight contact,I built a custom 3 1/2 for the bow!
The smaller you go when building stabilizers, the smaller the chambers and less performance you get,a hunting setup require`s less stabilizer for sound & vibration absorbtion because, most use a heavier arrow!
The 6" & 8" have very close to the same performance,when you drop down to a 4" there is a difference in performance! No matter what brand you choose,the smaller the stabilizer the less effect it will have.
Hope I helped awnser your question,look for there to be a smaller Stealth on my site some time in the future,I`m just not sure whether to go with a 4" or 3 1/2" .....guess there is a need for both!