I haven't heard about a symposer delete plate leaking, but it's like anything with a gasket seal, lol. Most of the kits are around $30 USD and have both a plug bolt and a nipple for running true vacuum to the BPV. I had the center hole plugged until I got an aftermarket bpv... Going straight from the boost control solenoid causes it to vent pretty much every time you lift off the throttle (even light throttle and got very annoying very quick, lol). Just my opinion that it's nice to have the option. Use some Teflon tape or equivalent seal around the threads and shouldn't be an issue.