I have all four. I should say, I had all four (glass is fragile). Each has its advantage IMO. Delrin is usually the economic choice. And, for folks who are hyper sensitive to metallic taste it is the clear choice over either stainless steel or aluminum. I'm a bit sensitive to metallic taste. But, the stainless steel gives me no problem, while the aluminum does ... YMMV.
I loved my pyrex tips. Stainless steel (mine are from Super T) are a lot more durable though and work nearly as well as glass IMO. It should be noted that the Super T SS T Tips are the Rolls Royce of drip tips, not all SS tips are equal.
If you go for pyrex I'd recommend them for at home use only (expensive lesson learned).