Brick,
I was using the HDB before getting the Cobalt Solid and the HBD was very predictable and drilled 4 X 3 3/8. But I liked the reaction on the Cobalt Pearl so much I tried the Cobalt Solid.
I use to play down and in then got caught up in a wood house that dried very fast and started to swing the ball everywhere. My average suffered. I have learned to take what the lane gives me and on a synthetic house shot, that is pretty much down and in. With the back ends fresh, the Cobalt Pearl has been awesome but the Cobalt Solid was too squirty n box condition. It wasn't until I used a grey scotch brite pad on the Cobalt Solid did I finally see the control and power of the Cobalt Solid. I don't track too low but my stract is not considered high (4 7/8 and 3/8 up. I seem to do better with solid bowling balls that are not skid flippy. I also have the EU and that ball is a monster when the back ends are fresh but also could not handle the cary down. A litle too unpredictable for me, but a powerful ball n the right hands.
Hope this helps, if you need more info, please message me.
Barry