I bought the 70s and immediately regretted it since I had them maxed on day one. Added the upgrade kit a couple of months later.
I think the only thing to review here is the upgrade experience, since the upgrade kit is just 3 more plates for each side of the DBs. It's smooth. You ned to unscrew the cradle from the stand (if you have it), remove one screw from the bottom of the stand to be able to remove a spacer piece, and then put the new weights in place and screw the cradle back to the stand.
Performance
Value
Build Quality