i would rate tempered glass over everything. its virtually scratch proof...cleans easily. can easily be tinted with window tint. hard to break... but when it does, wooo boy. must be custom ordered in th3 exact size you need. cannot be cut later.
next, plate glass. same benefits as tempered glass being easy to clean but easily cut and sized. will crack into shards if impacted or stressed
next, plexi / acrylic. it can be cut fairly easily. and its pretty tough and resists scratches.
lexan /poly carb. it cuts fairly easily with power tools but will scratch the first time you wipe it with ANYTHING. but tough as all hell. resists impact... wont shatter.