I went from HBI springs to CZCustom trigger + trigger job. Absolutely no comparison. CZCustom smokes the springs.
If you don't want to spend the big money though, the springs are an awesome bang for the buck. HBI springs won't shorten the pull, shorten the reset, break crisper and be overall less mushy like the CZCustom, but it will be a lighter pull. Not as light as my 3# CZCustom pull though.