A few weeks back I started playing almost exclusively on hardcore....and woah going back to normal is pretty awkward.  I thought it'd be rough...but holy shit my reflexes are beast like now.  Your margin of error in hardcore is much smaller and it shows when you play on normal...opponents seem to stare at you for hours before taking a shot. 
  One thing I've found though is on hardcore I almost always play with a silencer, and feel it's a necessity.  But in normal games I feel like it leads to too many assists/stolen kills.   Kind of makes sense though, since the drawbacks of a silencer are negated in hardcore.   It seems people are especially adept at seeking out the source of gunfire on hardcore, and hiding the muzzle flash is the biggest advantage probably.  
 
I mainly use the FN FAL + silencer with the Python + ACOG as my secondary.  Both guns can 1 shot kill, and with second chance you can strike back at super long range.  Python + ACOG is basically a pocket sniper rifle with no reticle drifting, and I've found it to be exceedingly accurate.  I actually think there should be a little reticle drift added if you have an ACOG on the python, because it's just too easy to make long shots while strafing or while in second chance.

I like barebones because it reminds me of simpler times.  
 
To many laggy players that make hardcore feel cheap when you kill or get killed.

" I like barebones because it reminds me of simpler times.  "

" @Arkasai: Annoyingly there isn't just a perks no killstreaks mode is there? "

My thoughts, remove the Prestige Playlist (pointless in my mind as your Prestige level is not reflective of your skill) and replace it with a Hardcore Barebones Playlist.

One group of friends I play with go exclusively on Hardcore, the other is only Core. I found the same thing, switching from hardcore to normal improves your reflexes. I do struggle though when first switching over to Hardcore after playing for a long time on Core.

It depends on the game mode. Hardcore search is great, but everything else is better in regular. 

One thing I've found though is on hardcore I almost always play with a silencer, and feel it's a necessity.  But in normal games I feel like it leads to too many assists/stolen kills.   Kind of makes sense though, since the drawbacks of a silencer are negated in hardcore.   It seems people are especially adept at seeking out the source of gunfire on hardcore, and hiding the muzzle flash is the biggest advantage probably.   

I play on hardcore as much as possible. It's a much more enjoyable experience for me with a cleaner HUD and quicker kills.

" @Arkasai said:

One thing I've found though is on hardcore I almost always play with a silencer, and feel it's a necessity.  But in normal games I feel like it leads to too many assists/stolen kills.   Kind of makes sense though, since the drawbacks of a silencer are negated in hardcore.   It seems people are especially adept at seeking out the source of gunfire on hardcore, and hiding the muzzle flash is the biggest advantage probably.   

^^ I am never using a silencer in hardcore. The way I play I use a famas with dualmags and put hardend pro on. SHOOT EM THROUGH THE WALLS!!! ;) Works perfectly. Cover is practically nonexistent and with dual mags you can empty a clip into a wall two or three times (and kill one or two enemys in the process) and still won´t have to worry about ammo.  "

i only play hardcore search when my friends and i just want to team kill each other.  otherwise i haven't really given it a chance to play seriously. 

I only play HC.  I haven't played a standard match in a long time.  I'm on the PC and only choose HC tactical servers where you have to crouch and can only run when under fire.  More often then not they also have a no second chance rule too, which is good in HC because that perk becomes way too powerful.   
 
My main setup is M16 + silencer with Ghost, Steady Aim, and Hacker.  It probably helps that on a monitor you sit a lot closer, but I find it stupid easy to get hip fire kills with the M16 in HC with Steady Aim.  If they are in the middle of the screen, then they are dead.  It has saved me many times. 
 
I feel like I am done with the traditional CoD gameplay, so the only way I will play it is if I can play it like it wasn't CoD.

Hardcore was the only thing I ever played in CoD4 and MW2 (I haven't bought Blops). Silencer always, for some reason it felt like I gained accuracy from it even though I know that isn't true. I tried going back to normal but having to empty a whole clip into a dude (it felt like it in comparison) just felt really awkward.

" It depends on the game mode. Hardcore search is great, but everything else is better in regular.  "

" @Arkasai: Annoyingly there isn't just a perks no killstreaks mode is there? "

Hardcore will never die,but you will ;-)

" I only play HC.  I haven't played a standard match in a long time.  I'm on the PC and only choose HC tactical servers where you have to crouch and can only run when under fire.  More often then not they also have a no second chance rule too, which is good in HC because that perk becomes way too powerful.    My main setup is M16 + silencer with Ghost, Steady Aim, and Hacker.  It probably helps that on a monitor you sit a lot closer, but I find it stupid easy to get hip fire kills with the M16 in HC with Steady Aim.  If they are in the middle of the screen, then they are dead.  It has saved me many times.  I feel like I am done with the traditional CoD gameplay, so the only way I will play it is if I can play it like it wasn't CoD. "

"  @X19 said: 

"  @Arkasai: Annoyingly there isn't just a perks no killstreaks mode is there? "

Another thing I wish they did was make "classic mode" (classic COD4 killstreaks) perks and attachments. I really don't know how they can call it classic mode without 2 things integral to the COD formula. "

" @President_Barackbar said: 

"  @X19 said: 

"  @Arkasai: Annoyingly there isn't just a perks no killstreaks mode is there? "

Another thing I wish they did was make "classic mode" (classic COD4 killstreaks) perks and attachments. I really don't know how they can call it classic mode without 2 things integral to the COD formula. "

I think when they mean classic...they mean like COD1,2, and 3 multiplayer.     "