Any feedback on JP Enterprises 5.56 uppers ?

You cannot go wrong with anything that John Paul & Company make from small parts all the way up the line to their complete rifles (naturally...that includes the upper you are considering)! ;)
 
Like what has been said. Tip top of the line. Every jp barrel I have had has shot well under a half minute with match ammo, and a half minute with blasting ammo. Jp really knows how to make an ar perform at the top of its potential, from gas systems to bolt carriers to barrels to handguards, I can't recommend them highly enough. Great guys to talk to on the phone too.
 
A quick search will turn up many threads speaking to the quality of JP products and service. John also fully supports the shooting sports through match sponsorships and frequent participation in both long-range and multi-gun events. Doesn't get any better than JP Enterprises.
 
Well I guess everyone has already summed it all up, JP Enterprise makes world quality firearms that shoots every time you pull the trigger and hits exactly where you aim it. But what makes them really special is all the Love that goes into them, they are a thing of beauty.
 
JP Ent., anything I've ever gotten from them over the years has been top notch. I barrel my own uppers, but I only use their carriers and bolts anymore when I can help it. They work way better than any I've ever used and I consider them well worth the extra price.

In fact, I've never heard anyone knock their stuff, ever, and that's damn rare in the shooting world. Some don't like the "cosmetics" of them or may not like a certain feature (I don't care for side charging handles) but they've generally got something for everyone.

They're also notorious for trying new things like those finned barrel heat sinks and low mass carriers and that funky looking brake.