I actually have three different types. I like the Delrin because it doesn't heat up, but the juice takes a while to slide down, and it doesn't fit snugly in all attys. I mainly use it with my "traveling" Ego I take to work.
My aluminum tip is fine, but has a small lip about 1/4" down that I don't really like. It can get really warm - but I've only had one time that it became so hot that I got a blister on my lip. Annnnd let's just say alcohol was involved
I
love the Stainless steel Super t-tip... It's smooth, and feels good against the lips.

It's worth the extra money. It's gotten warm, but never hot. I have the longer one - and I plan on getting the shorty.

Oh - and I've never taken any of them off to drip. Never even thought of it.