Last night I discused this thread with one of our colleagues...
Something makes no sense...
Why do people still using Y connectors in America?
According to known design techniques, Y is much more fragile than T, because of the 90 degrees angles that can be much ticker without compromising the water flow or the size of the part.
I've been using T connectors since the first time i nedded one 30 years ago and NEVER had a leak.
By the way, I did something stupid but it still working without leaks. I used a standard PVC (not the CPVC, designed for high temperatures) T connector on the HOT WATER pipe (and my hot water is really hot, almost boiling). Something I learned with my former boss, if it's working ok, never touch or try to fix it.
My installation has 8 T connectors installed sequentially, the pressure is amazingly high (70 MCA, have no idea about how many PSI, but enough to fill a top loader in a few seconds and the limit a solenoid can resist is 80 MCA) and I NEVER had a leak or a damaged connector.