""If"" you have snails in your sump "or" a refugium before...got ya! So if neither we are good to go!
Just looks like good information to me in that wall of txt. That snake oil he is selling must be good for doing it for so long and so many products he sells as well.
So, again.... there is a "slight" difference between your old system and his as stated even if so small. For me, ive seen them working with no issues, havent heard any others with issues.....I'm a number kind of guy, so if there is a few out there i will say so. On Mike's grid about a year ago, power was shuting off and on for about week for whatever reason FPL had going on....about 2/3 times a day in the evening time.... Not one issues in the start up of the siphon. The only problem he had was with 2 of his koralia. One was spinning the other way and another with clicking trying to start when power came on.
For the record- If it was me i will drill that **** thing. OP doesn't feel comfortable enough in doing so.... cause what "if" he cracks his glass. If me, I will save and have someone do it for you. Check with an LFS if they will do it for you. Around here is about $10- $20 range for 1-4 holes. Check and ask it wont hurt. They made come out to you for a little extra or you are gonna have to take the aquarium to them. Or buy some glass and do a few test before getting your feet wet if you go that route. Even a sump on the freshwater side is awesome and the way to go IMHO. With a nice wet/dry and you are set..Good luck!