Economical replacement rocker arm set?

So I drove a longer distance today that included back roads and highway. Maybe I am over-sensitive to the car feedback when I change things but I have this feeling like I am down a little bit on power. It is just a feeling, nothing like "whoa, I lost power" but more like, "huh, I wonder if there is any chance that I might have lost 10hp".

So, please put me at ease so I can go back to enjoying my car. Is there any way that these new adjustable rockers could have lowered the power output of the engine? I am thinking that the only way possible would be a reduction in the lift of the valve thus reducing airflow. Seems plausible that I over pre-loaded the lifters and thus they aren't pushing the valves open all the way. However, I would expect that this would show up in a different idle or more dramatic power loss, or something very noticeable.

I think I am making this up but wanted to ask.