sorry had issues opening posts last couple days and didnt see prev posts let alone know if mine got posted

No need to apologize.

maybe a sliver of prev dif material (not melting) was moving around in hot end nozzle causing it

I can appreciate your enthusiasm.  However, it would most likely be of greater benefit to other users if you would take the time to read my previous post.
The whole purpose of this thread is to help others (in a fun way) by posting pictures of failed prints with known causes and solutions.  I would love to see some posts from some of the other more advanced users as well.  So if you have an example of a common failure that you (with absolute certainty) know the cause and solution, feel free to post it.

I chose this failed print because bad connections are one of the most common problems out there.  They aren't always easy to find when they are intermittent such as this one.  When this first happened I thought the exact same thing as Hazer, must have a clog!  I new it wasn't dirty drive gear as I have a Bulldog XL and have never seen it strip the filament.
So if you run into problems during a print that is going to cause a failure.  Don't just stare at your printer and hope it all works out.  Instead bring up your temp chart and verify things are as they should be.

Hope this helps someone

As I always say "If it isn't fun why would you do it"?

The fact that the top layer is incomplete but is not in a predictable pattern suggests a random problem with extrusion. My guess is a partial clog or extruder gear problem (gummed up or tension incorrect). Your perimeters are too straight to be an X-Y problem, so there is no explanation for why the infill/top layer is so jagged.

Getting close... And as always a helpful post Hazer.

maybe its printer specific, what brand is printer?

It is not specific to brand but to answer your question that was done on an SD3. Check signature for mods.

I've noticed that I need to push the filament feed rate up to double or more of the "correct" calibrated setting otherwise I get similar gaps in the surface of my prints. I'm starting to think it varies with every filament, and I need to calibrate temps and feed rate for every one. Is that how it works?

You should calibrate with each and every spool, I doubt that is your problem though.
If you need help figuring that out let me know.  Could probably fix that in a few words.

My guess is either temp setting or maybe an issue with belts...errr....fishing line

Nope... Try again