P: Slow UI when using Mac and Custom Display Profile

What software product do you recommend that is demonstrably bug free? 

"Actually the only thing worse would be to get a new version with a fix for this bug, and three more new bugs that affect even more users. "

I agree, and based on the evidence of recent releases, that appears to have a probability well north of 0.

Both Displaycal and X-rite's product(s) (depending on the functionality unlocked based on the price for the instrument) is superior to anything from the Spyder folks, but it's their hardware that's just so-so, at least many offerings in the past. 

Thanks for your very detailed and useful response. 

Displaycal is free. It's far more complicated and time consuming to use than the Colormunki software I got with my device from X-rite. I can't even remember what software I used with my older device I had before the colormunki. The X-rite software is very basic, and takes very few color readings. I think the calibration from that was good enough to my eye -- I made some very successful prints with calibration from it. The Displaycal is good, probably much better than the X-rite software was, but also perhaps more prone to user error creating a bad setup and certainly possible to spend more time doing it. Opposite from the problem of the X-rite doing very few color readings, you have to be careful with Displaycal not to have it do too many. It will take a very very long time to process if you do too many.

For all it's a 'high priority item', there doesn't seem to be any sense of urgency around the issue

The key word above is "seems". 

What on earth is taking so long?

As much of what can be said publicly has answered that question. 

Hypothesis: a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.

"If the facts don't fit the theory, change the facts". -Albert Einstein

For scientists, a theory is a well-substantiated explanation of an aspect of the natural world that can incorporate laws, hypotheses and facts.

Actually the only thing worse would be to get a new version with a fix for this bug, and three more new bugs that affect even more users. 

Fair points, though the 'releasing information' issue with most companies is related to revenue recognition, but that's not the case here as it's not revenue impacting (i.e. there's no material pending sales that would be impacted by sharing a target date).  They could (and should), but they won't.

For all it's a 'high priority item', there doesn't seem to be any sense of urgency around the issue - it's been around for multiple months, and the last status update was over a month ago.  What on earth is taking so long?

Hypothesis: they have a fix but are sticking to a predetermined release schedule and it's bundled in with the next batch of code scheduled to drop on a particular future date.  We'll know if that's correct when we either get a patch just for this fix, or the fix is included in a batch with a bunch of other stuff including new features.  Words escape me to describe just how anti-customer the latter would be.

The only thing worse would be to get a new version without a fix for this bug.

I have a sinking feeling though, that while this bug is making things worse, I'm still going to have the stuttering library problem because of the other performance issues...oh for a competitive alternative.  iOS and Android are both better because there's a viable alternative.  Wish there was something that truly competed with LR.

As to "obligations" and ETAs, some here should examine the EULA they all agreed to in order to even install/use the product. 

This is specifically relevant:

9. Disclaimers of Warranties.

 

9.1 Unless stated in the Additional Terms, the Services and Software are provided “AS-IS.” To the maximum extent permitted by law, we disclaim all warranties, express or implied, including the implied warranties of non-infringement, merchantability, and fitness for a particular purpose. We make no commitments about the content within the Services. We further disclaim any warranty that (A) the Services or Software will meet your requirements or will be constantly available, uninterrupted, timely, secure, or error-free; (B) the results obtained from the use of the Services or Software will be effective, accurate, or reliable; (C) the quality of the Services or Software will meet your expectations; or (D) any errors or defects in the Services or Software will be corrected.

And I did not add the bold font, Adobe did in the LR EULA, I suspect so those few who do read it, see it. 

General Terms of Use

Do you find Displaycal to be superior to the Spyder5Pro in some way? On Windows I'm not affected by the slowdown, just wondering if it's a superior calibration tool. Something on which to spend my stimulus money.

I don't print so only interested in calibrating my 4k IPS monitors from BenQ and Dell. They are both 99% sRGB and ~75% RGB. 

Yes I've done a lot of searching and find opinions going both ways. The net from the reviews is that it doesn't matter unless the monitors are superior than mine. 

Adobe's best interest is probably to get rid of this as soon as possible. Just like us, but for different reasons. And I can understand they can't publish an ETA, it's not a problem of parcel delivering.

Now they started to deal with it, the more time they spend, the more money they spend (and the less they earn dealing with more profitable tasks).

After all, it might be weird to say, but it's a kind of win-win situation.