To be honest I never believed in these scripts boosting your performance by X% because of 20 lines of bash. I don't believe it'll magically give a device a performance boost without any losses. The hardware of a device has it's limits, and you can increase those a tiny bit by sacrificing other features such as people wanting loads of free RAM (because they think it makes their phone faster) but the sacrifice is multitasking. Since those scripts basically kill everything that runs in the background except for the launcher.
Other than that, do you feel your Z1 needs any of those scripts? Are games lagging for you? Are you not happy with the performance? I don't see any gain to be had by installing any of those scripts which are in my opinion BS anyway. The Z1 is a very fast device and if it is lagging for you I think you have a/multiple CPU hogging apps installed.
"However, if you put any trust in Benchmark Scores you could use them
to prove that dancing naked for 5 minutes in your garden affects device performance" - Chainfire