Have a look at the first thread in the Getting Started section, lots of info there. Also check out the build areas, many builds have the makers names in the titles, you can see the different makes, how they look and sizing.
You will have not issues with RS or AP
Also consider what version of Stormtrooper you want to build, one make doesn't suit all. List of CRL's is here https://databank.501st.com/databank/Costuming:FISD_CRL