They both have their benefits and detriments. There is no "better". Like with everything else in life, it depends on what you are doing, and what you want out of it.
For the occasional shooter, oil works perfectly well and has for a LONG time.
Most people will use oil like Hoppe's or Remoil (or similar). It's easy and cheap, but it eventually migrates away from where you put it. Gravity will get you every time. It is also less cold sensitive.
Some like greases because of the feel, and the fact it doesn't evaporate or run. But gets pushed out of contact areas. Grease can thiken in cold weather.
Some like products like Slide Glide that bridge the gap between the two, but are harder to find. They sometimes offer multiple thicknesses if lube to tailor to the type of weapon or it's purpose.
Still others use non firearm related products like Mobil1 even. There may be issues with that though from additives in the oil and long term exposure to skin.
For the occasional shooter, oil works perfectly well and has for a LONG time.
Most people will use oil like Hoppe's or Remoil (or similar). It's easy and cheap, but it eventually migrates away from where you put it. Gravity will get you every time. It is also less cold sensitive.
Some like greases because of the feel, and the fact it doesn't evaporate or run. But gets pushed out of contact areas. Grease can thiken in cold weather.
Some like products like Slide Glide that bridge the gap between the two, but are harder to find. They sometimes offer multiple thicknesses if lube to tailor to the type of weapon or it's purpose.
Still others use non firearm related products like Mobil1 even. There may be issues with that though from additives in the oil and long term exposure to skin.