Yes it will work in any standard ar15 .223/5.56 .300blk
Yes. The LANTAC Enhanced Full Auto Style .223/5.56 Bolt Carrier Group will fit and function in any Milspec AR15 chambered in .223, .223 Wylde, 5.56, and 300 Blackout regardless of barrel length or gas system length.
The LANTAC Enhanced Full Auto Style .223/5.56 Bolt Carrier Group will work with the JP SCS.
Yes, it will.
Yes, it will function flawlessly in Semi Auto or Full Auto.
Yes, it will work with all barrel lengths and gas systems.
You can if you would like a very high quality replacement, but as long as you have a quality, standard AR bolt carrier group that is full-auto profile, it should be just fine.
If it allows the use of Milspec BCG's.