As a tried and true TB-03 fan, I was looking forward to the release of the TB-04. Albeit, I was not aware of what this rig might look like or what changes to suspension geometry, balance, adjustments, etc. The TB-03 has been fairly dominant for GT-3 in the past couple years, and the interest in the chassis as seemed to grow. I recall people telling me to scrap my TB-03 in favor of the TA-05. I had two '05s and have since sold them, as the shaft drive (IMO) is a better choice.
As I reviewed the TB-04 CAD drawings, the spoiler here is the addition of one more bevel gear set in the driveline. This this the weakness of the driveline and now there is one more set to shim up correctly. Not that this is hard to do, but the added friction and drag will add to reduced speed (or power loss).
The 6 degree caster hub looks pretty good. I have run the 4 degree, and the 2 degree certainly offers more steering so the 6 degree will provide a little more stability. But, the quickness of 4 or 2 degree caster provides the responsiveness that helps the car get through the technical sections. Maybe I'll keep a 4 degree set on hand to test the responsiveness.
The other update is the shocks. I like this option of being a short stroke but similar volume. This may not change a lot other than the flex of the shock shaft. Less flex potential seems to be a good thing.
Overall, I would certainly like to have one. I think my TB-03 will still be better, but there could be improvements that are not obvious which will translate into quicker lap times. Time will tell. I hope the TB04 is a better hit than the TA-06. If not, the TB-03 and TA-05 will continue to be the chassis of choice.
Just my two cents.
EBR