I am also running CH95s, and overall am very happy with them, except - sometimes I feel like they have too much air in them, even though they are inflated to a "reasonable" 35psi (considering they are rated at 51psi).

Mine are oversize (235/50-18 front, 265/45-18 rear) on a 92 500sel, but I find the same symptom that you do. I have also replaced all required bushings, etc.

It is a "shudder" (where the tires seem to "pound" the suspension), and I was thinking that there is some other worn suspension component that I have missed replacing, but maybe it is just the nature of these tires (where they have a sharp threshold between the normal "soft" ride, and a much sharper ride when negotiating a bump).

Just my thoughts - if my car were new, then I would be more confident that it is the tires and not some other suspension item.

-David
92 500sel (not for sale)
86 560sel (sold last week! finally gone!)
85 535i (to be sold this week)
82 QPorte (would be sold, but no one will buy it...)