This forum has convinced me that I probably "need" an MP5 clone of some sort.

Question is, SP5K or one of the clones.  If a clone, which one and why?

TPM Outfitters. Arguably the best American made MP5s. Great people too.

http://www.thefirearmblog.com/blog/2016/06/09/tpm-outfitters/

SP5K only if you need/want HK engraved on your receiver.

MKE

I bought the Sp5k for a few reasons,
-it was a opportunity for me to have a "real" hk
-I hear reliably problems with some of the clones. I don't have the patience to mess with a problem gun.
-the dealer had one in stock at a good price $2150
-there are many aftermarket mod parts if I want, and don't need to worry about compatibility
-hopefully resale value or possibly appreciation will be there.
-it came in a cool case ;-)

I picked up an SP5k on a whim and wish I would have bought this platform years ago.  Showed up at a gunshow to grab the wife a new carry pistol and there it was.  I walked out with it for $2100 and couldn't be happier.  MKEs and Omegas have an excellent reputation and cost about $400 to $500 less.  If you plan on utilizing a suppressor, I would definately go clone and skip the K as a barrel swap is very expensive.  If you are not, the little extra money, rollmark, and resell (if that's a factor) is what you have to decide on (I do not have much 922r knowledge so can't help there).  In short, after shooting it the gun is absolutely amazing.  I shot it side by side with my MPX and the MPX was sold 3 days later.  I'm now looking at clones and researching other configurations.  This was one expensive trip picking up a Walther PPK for the wife but I am sure happy I did...... Her on the onther hand......

After a couple of days of research, I would pick the HK again.

Here's a bad pick after adding an SB Tactical brace.  

Paddle release. HK totally dropped the ball on that one with the SP5K. I'll take my four custom-built 50+% factory parts HK clones with paddle releases over an HK marked receiver gun without a paddle release any day (plus my 5K clone has got a Navy 3-lug/threaded barrel and ambi trigger pack). Was it cheap? No. Do I have regrets? No. Resale value? I'd sell a kidney, first. I wanted something as close to an MP5KN PDW as possible, and going with an HK oddly (sadly) wasn't good enough.

I got an sp5k due to the grail gun factor, but if it was for strictly practical purposes I would probably look at a clone for the reasons mentioned.

paddle release can be added though no?

and the SP5K does not come with a threaded barrel?

It adds like 125-150 onto the cost that is already too high. The gun also needs to be refinished then.

Yep. No threaded barrel. Replacing the barrel with one that does will cost a mint.

Don't get the SP5K.

I would buy the Omega first followed by the MKE.

I shot mine today and it was ....awesome! So glad I got an original insted of the clone. Yes the mag release can be added as the threaded barrel but it is expensive. If those items are important to you, the clone will be a great option. Hk couldn't export them from Germany with those options on it. I couldn't be happier with mine, runs flawlessly!

Just a comment about what was said above; depending on who does the work changing out your barrel, it does not have to be refinished.

Michael's Machines did my SP5K and installed his own production 3-lug barrel. No refinishing required and it looks great.

Same thing with the paddle release install.

Shot my MKE SBR with an HK today and honestly, unless your fixated on a roll mark and/or reselling your gun, there's very little that favors the HK.

Very nice gun, however virtually indistinguishable next to the MKE that comes with the paddle and 3 lug. That and I'd never care for these guns regardless who makes them unless they're SBRed and I have no interest in selling any NFA item.

My guns get shot a lot, my safe doesn't know what a "queen" is. Accuracy, reliability and finish? No difference. That being said, I'm really happy HK released these, it's a BIG step in the right direction.

Dakota tactical is the only game in town if you decide that you want to go the clone route. Their products are exceptional and highly sought after. The finish and build quality out distances MKE, Atlantic Arms, and POF.

Dakota Tactical

Honestly, cost aside, buying an SP5k and having a barrel swap done makes no sense IMO.

You buy the HK because it's an HK, if you are going to start swapping parts, just buy a clone.

no, just no.

Agreed.  The pricing on those is crazy.  They won't hold their value.  My Zenith/MKE Z5RS has run flawlessly.  
If I was in the market for a K Gun I would go SP5K.  Once you pay to add the 3-lug barrel and paddle release you are at what Joe wants for his gun anyway.

I looked at both the HK and MKE; went with a MKE 5RS. The reason I went with the MKE was the little extras plus the fact it one of two authorized licensed HK MP-5 products made on HK machinery and blue prints, hence no reverse engineering. Would I buy a HK SP5? Yes, if the price was right I would buy my third clone