Pros and cons of solid lifters?

For me, it's a question of the owner and the need. Solids will make more torque than a hydraulic of equal size. They tend to have flatter power curves than hydraulic again, of the same size. That's due to the extra duration and ramp speed the hydraulic (and hydraulic roller for the same reason) simply can't have and function. The lash will change slightly while the new engine settles in. But after a few thermal cycles you should be able to set and forget. Once a year if that. A performance hydraulic may need the same rockers and may be as noisey as a solid anyway. So at that point it's almost a why bother deal.