It used to be excellent, but with recent kernels above 5.4 it messes up sleep and suspend functionality. System freezes after waking up from sleep, and removing tlp solves everything.
I did not notice a really difference in my laptop temperature. I recommend using a tool called auto-cpufreq which works better, or editing manually the system cpu configuration files for reducing the minimum CPU frequence, disabling turbo and change the CPU scalling governor.
Download tlpui from http://ppa.launchpad.net/linuxuprising/apps/ubuntu/pool/main/t/tlpui/
to have gui: https://www.linuxuprising.com/2018/11/install-tlpui-in-ubuntu-or-linux-mint.html