Upgrade to LS50s from Q150s for near-field? Something else?

[Ultrasonic]

No. Was never really interested in buying due to rather subpar measurements (again, not just FR/tonality in a nutshell) and cost effective construction with plastic front baffle (in normal budget case there's MDF baffle underneath).
All mentioned above is actually fine, but... HYPE. Not just excessive hype (okayish speakers, on par with other budget models, nothing to hate, nothing to rave about) but those who dare to dislike/criticize these (and KEF on youtube BTW lol) receive feedback which sometimes is nothing short of agression. Are these really sort of holy cows?

I totally agree with you, however, there's a night and day difference - while BM5As are captured well enough and sound "right". How could that happen? Except it's all made up by Kali haters lol.

Nothing wrong with you not likely something you've actually heard but basing your opinion just on a video like that is, frankly, nuts. For the record, what I hear (on some admittedly not-great headphones) is nothing like what I experience from either LP6 v2 or IN-8 v2 speakers actually in my own home. I don't think they're perfect/amazing but I do think they're good value for money. If they truly did sound as awful as you think, would people would buy them? Or indeed would the engineers at Kali have put them on the market? Of course not.

 

[mtaz]

Well, after all this... I think I may end up keeping the Q150s.

After applying room correction (and making a couple of minor tweaks to that curve), and putting the speakers on the isolation pads, which raised them a couple of inches and pointed them slightly upwards, they sound a whole lot better than when I first got them.

I'm sure that the speakers that I'm looking at for twice the price would sound better, I'm just not sure that they would sound enough better to justify the cost. And I have my headphones here at my desk also (Audeze LCD-X and Sennheiser HD 600).

One thing I've noticed about the KEFs is that they aren't particularly kind to poor recordings. I think this may have also played a part in influencing my initial opinions. My Page remaster of Led Zeppelin II arrived today, and it actually sounds really good. I also played a few tracks from Massive Attack's Mezzanine, which is famous for having some really deep bass, and this also sounded better than one might expect from speakers of this size and price. (BTW, I saw that they are now on sale at Crutchfield for $300/pr.)

 

[Ultrasonic]

Good result - enjoy .

 

[uwotm8]

After applying room correction (and making a couple of minor tweaks to that curve), and putting the speakers on the isolation pads, which raised them a couple of inches and pointed them slightly upwards

What a nice plot turn! Jokes off, judging speakers without basic actions of properly setting them up can lead you nowhere.

they sound a whole lot better than when I first got them

Consider they just got burned in a bit. What if audiophools don't lie and it's a real thing?

I'm just not sure that they would sound enough better to justify the cost

That's eternal fight in any audio-possessed soul

the KEFs is that they aren't particularly kind to poor recordings

And that discussion is eternal as well. There's two points and both are particularly right:
1) Good system requires the best recordings, poor recordings sound bad on a good system - even unbearably bad
2) All recordings (except utter trash) sound at least pleasing good system while you hear advantages of better recordings
Oh, third option - it exist
3) Some system make everything sound sweet and pleasing so you just listen to music
From my humble experience:
Type 1 is actually a bad system what will lead you to chosing "right" track and avoiding a lot of albums if not even genres because they "sound bad". Definitely the case for some fullrange-driver based systems but not only. I think I avoided owning that type.
Type 2 is a true decent speakers, analytical yet pleasing, right tonality and so on. Mid range Adam and Dynaudio, I guess Genelec as well.
Type 3 can be either sort of clock radio or just a nice budget speaker (Adam T and old Castle speakers I owned years ago) or ultimate hi-end madness beyond all typical wooden boxes (MBL omnipolars, for example). Whatever it is, it just plays everything you throw in and somehow you don't focus on any caveats at all. The downside for budget options however is everything sounds rather the same. Like a perfect fast food.

Anyway, keepng your system is the best decision if you're uncertain about need of upgrade at all.

 

[uwotm8]

If they truly did sound as awful as you think, would people would buy them?

Phislosophic answer: because most of the people actually don't choose by themselves. And because for a lot of people a pair of sub-$300 apeakers (could be LSR 305S or Wharfediamonds) is their first serious buy. It goes like "hey Reddit, whatta buy, my best speakers so far are my laptop speakers?" - "get Kali, they're good" - "wow really! so much better than laptop"
Should I tell how many people buy Yamaha home cinema sets and enjoy them as well?
So, that argument is flawed. Maybe not as much as YT "listening" tho.

I do think they're good value for money

I agree. I just don't think they're exceptional as a lot of people praise.
The IN lineup, however, is exceptional as the only current budget 3-ways.
There was 3-way KRKs and Thomann's Swissonic X8, both gone.

Talking about awful - really awful speakers are pretty rare (there's a dedicated brand tho, it's called B&W; joking).

Will try to reach Kali just to check them IRL.