I’m generally of the opinion that if there is no hole in the boot for the grease to get out, then there is also nowhere for water to get in, and the main point of the grease is to keep contaminants and corrosion away, so leave it all sealed the way the factory did, and it should be good. Having said that, we are now getting to a point of taking what you can get. Multiple times lately I have ordered full sets of the same brand parts, only to have a mix-match of greaseable and non-greaseable, so now I just order a name brand and take what I get. Lately the Mevotech stuff has been pretty good, just make sure to get the better line cause they are named kind of deceptively. The “original grade” are the cheap junk.