Hydraulic lifters do offer some advantages.
1.They stay adjusted for a long time.
2.They are quiet.
3. There is in practical terms a bit softer transition on the cam.
4. Possible, less wear on the rocker arm.
Mechanical lifters will follow the cam profile as well as the valve spring pressure allows. However, I don't run an aggressive cam profile, I have an inline six. It does have mechanical lifters...So why? 'Cause that is what it came with. That is why. The issue is an esoteric one for most of us. If I needed to replace the cam and my engine was newer, I would consider the change when I put in the new cam. My 235 is an earlier version, 55-57 so I would just buy a cam and matching mechanical lifters if I needed to do do so. Not much bother to adjust the mechanical ones any way.
