fakeXsound: I prefer PC(my primary system is such), but I have a few Mac's laying around. I'm assuming you suggest using the Mac since you mentioned Thunderbolt and Logic.
Dochartaigh: I have a lot of records that were only released in that format. So no proper flac/mp3's around.
Nope, no need to use a Mac. It's just what I use. Any modern audio interface should be compatible with both platforms. The only caveat would be to make sure your system has a dedicated audio processor (as opposed to the CPU taking over those tasks). If you don't have one on your motherboard, you can get a PCI one. Back in the day, a Mac may have been a technically better option out of the box due to FW800. But USB 3.0 has enough bandwidth for a single stereo source.
Reasons for digitizing a vinyl record:
1. Record was only released on vinyl. I don't know about other music, but this is somewhat common in punk and hardcore, which had a lot of 7" records that were never published on CD.
2. Vinyl records have usually been mastered differently to account for the format's differences from digital. This creates a somewhat less articulate overall sound. This can be good or bad depending on your taste and the particular piece of music at hand. Think of it as the difference between a movie that uses grainy film stock vs. a movie that uses 8K digital capture. The film creates a soft, eye-pleasing looks, whereas the 8K footage is extremely sharp. Each has its place. You'd want something a little soft for something like jazz or blues or older rock stuff that actually sounds
bad on CD because the recording equipment and methods back then were so rudimentary. You'd want something sharp for anything modern or maybe for orchestral stuff, as digital lends itself more towards frequency separation (i.e., being able to hear each instrument on its own as opposed to being all sonically lumped in together). Personally, I buy CDs (along with high res audio versions of the CDs if they're available) and do not own a turntable, though I do buy the vinyl versions of my favorite albums. I would like to get a Technics SL 1200 some day, but I'd rather spend my money on more CDs at the moment.