OT: rough-riding kumhos?

[amalventano at sc.rr.com (Allyn)]

has anyone had any ride issues with kumhos (or any vibration issue that
ended up being tires - any brand of tires?).
im begining to think the rieger vibration is caused by tire compound not
being consistent.

symptoms:
- light vibration, feeling like slight tire imbalance, peaking at 67-68 mph
- vibration is amplified greatly by acceleration (i can actually control the
vibration with the throttle)
- 0 vibration in steering wheel, yet the vibration seems to be coming from
front-right (hard to tell for sure though)

corrective actions taken so far (not necessarily for this specific problem,
but changed nonetheless):
- engine mounts - 1 yr old
- front wheel bearings - 1 yr
- all suspension bushings - 1 yr
- wheels/tires mounted - 2 months
- wheels re-balanced - 1 month
- pass. half shaft - 1 month
- rear wheel bearings - 1 month
- front/rear rotors - 1 month
- alignment - 1 month (adjustments were made, no effect on vibration at all)
- all 4 wheels straightened and balanced within 0.08 oz. (dynamic), balance
verified by re-mounting wheel rotated to various positions on the balancer -
right before cincy
- dvr. half shaft - at cincy (i thought this licked the problem, turns out i
just didnt keep the correct speed for long enough).

when the wheels were straightened, i noticed that some other slight
vibrations had disappeared, leaving only the single vibration. this
vibration is now worse since the other vibrations are not present to help
cancel its resonance.

my intention is to try swapping wheels between the rieger and jetta to see
if the vibration follows. also, once i verify the wheels are actually
straight, i may have to do a road force balance or something like that. all
i know is that this vibration is driving me nuts.

any help/advice appreciated.
thanks in advance.
Al