Based on these tests Rust appears to be approximately 62.67% faster for mempool streaming than Typescript on the same hardware and node connection

cargo build

Start server

cargo run

Install Typescript

cd benchmarks
yarn install

Compare benchmarks for processing over 60 seconds

# Run Typescript for 60 seconds
ts-node pending-stream.ts & sleep 60 ; kill $!

# Run equivalent Rust code for 60 seconds
./target/release/pending-stream & sleep 60 ; kill $!