Is splash back protection more then anything man, but it does warp UV a bit. I see you got yourself a Spider Farmer though!!! You didn't say anything! Good buy brother! Anywho, the SF has built in water proofing, hence no shield/glass.
Personally, regardless of the UV interruption (very very minor for me) I kept the glass screens. Bang your head on it too, and you'll be happy it's there. Bust a diode or get it wet, you could easily be hooped.
Just my two cents man. Again, great call on the sf. You won't regret it👍👌