I admit I'm a vinyl junkie. Buy it all the time, although a lot of it is used oldies since they don't release as many current songs on vinyl any more. I have approximately 15,000 45s, and about 2000 albums. I also have about 1000 CDs and some cassettes and even some 8-track tapes. But yes, I am a nut for 45s. Even have custom built chests of drawers to hold them and others to hold the albums. I just bought another dozen 45s on eBay yesterday - claim to be new-old stock (unplayed). I caught this bug back when I used to DJ on our college radio station.
Sound quality is subjective, and condition is most important (the quality of your stereo system is pretty important too). I have some albums on both vinyl and CD that people don't have much trouble telling that the vinyl version sounds better... but typically these are CDs that were released not long after CDs became popular. The older CDs were made from tapes equalized for vinyl - today's CD releases are better because they are equalized from the beginning for CD. They upped the bass for vinyl and that makes CDs made from those tapes sound muddy. If your vinyl is scratched up or dirty it's not going to sound good.
Pretty easy to accumulate this much stuff when I've been buying it for over forty years, and a lot of it is pretty cheap used. Which also means my collection is worth a lot more in enjoyment content than in dollar value. Friends "dig it" when we have a party and I play DJ. Often their kids are mesmerized because they didn't even know vinyl exists.