Harbeth 30.1 or 40.1

I have not tried the SHL5's, but they have a similarly impressive sound to the 30.1's / 30.2's, but with a bit less dominant bass, and somewhat brighter highs.  It's very possible that they would be just as pleasing to you, though they don't sound as impressive on the YouTube videos.  Sometimes I think I might try them for a pair that have less dominate bass and brighter highs, though maybe a bit less rich mids. 

But, if you're after the sound that you hear in the YouTube videos, I'd start with the 30.1's / 30.2's and a matching integrated amp.  I think you'll find they will provide just the sound you're after at lower to moderate volume levels.  

They're easy to sell, if you want to try one of the others.  Or, you might end up keeping them and using them in another room.  

Once again, thank you very much for all the information.  To summarized all the pros and cons, logically, I should get the 30.1 and not 40.1, because:

1. For the price of 40.1, I can buy the 30.1 + McIntosh MA252.
2. I can’t afford to buy the 40.1 + MA 252 at the same time.  3. Since 30.1 is easier to drive, I can use my Almarro 318 for the interim, and that should yield better result than the 40.1.   4. The 40.1 is huge, much bigger and heavier than I thought.  I am concern to buy something so difficult to move.  And my wife won’t like it.5. 40.1 is harder to sell if it doesn’t work out.
6. 40.1 maybe too big for my listening area.
7. I listened to almost all videos I can find on Youtube, and I like the sound of 30.1 more.  It sounds more lively.  I guess it is because it is easier to drive.
8. If I want more bass for 30.1, I still have an option to add a subwoofer.

"listening to how they sound on youtube and like them"

sorry, i have to laugh and roll my eyes

While I've only heard the SHL5+ in stores (e.g. in Seattle), it always struck me as cut from another cloth, and aiming to do something rather different.  Just look at the drivers that it uses.  I heard the 30.1's at CAF and thought them excellent when driven with a high-powered tube amp.  It was the 40.2 iteration that sought to deal with the bass issues, over the 40.1, and are indeed much more domestic-friendly.  I don't understand the comment about 40's being too loud--there is a volume control, after all.  The 40's are large, awkward-shaped, and heavy, but that's what you pay not only to get the bass extension but also the wave-launch from the wider baffle that provides a more realistic impression of real instruments in real space.

I spent the evening yesterday at my friend's house listening to his 40.2s.  His room is fairly small (less than 20 feet on a side?  I didn't ask the dimensions).  Electronics were his Line Magnetic 805ia integrated, fed mainly by a Schiit Bifrost.  We also spun some records on his Pro-Ject Xtension 10 Evolution turntable with a Manley Chinook phono stage.  His room is heavily treated - absorption panels and diffusers on the front and side walls, diffusers on the ceiling, bass traps in the front left and back right corner.  There's a subwoofer in each corner where the bass traps are.

I first heard the Super HL5 Plus and the P3ESR at his house.  The 40.2s are much bigger, and they're beautiful.  He was running them with the grills off.  When we started listening, I don't remember what track he played first, but what first caught my attention was the imaging.  The center image was incredibly rock solid.  I felt like if I wanted to, I could stand up and walk up to the singer.  Her voice was coming from a spot right between the speakers and at the height of someone standing there. 

The 40.2s have more presence than the Super HL5 Plus, we listened at moderate volumes for the most part and the detail and texture of the voices and instruments was fantastic at low to moderate volumes.  When played loud, the music had a visceral impact, you could feel it as well as hear it, no doubt in part due to the subs. 

The 40.2s have a warmer presentation than the Super HL5 Plus, but don't give anything up in terms of detail.  The imaging and soundstage was almost holographic.  The one word that kept coming to mind while listening, was "texture".  They did the midrange so well and voices, guitars, and strings were rendered with a palpable sense of intimacy, as if they were there in the room with you, very "organic". 

If there was a downside to the 40.2s, the bass seemed less controlled and dynamic than when I heard the Super HL5 Plus speakers in his system.  I asked about the subs, and he said he had to lower the gain settings to integrate them with the bass output of the 40.2s (which I expected).  With the Super HL5 Plus and his subwoofer setup, the bass in his listening space was very dynamic, going from not noticeable to prominent in a super fast and controlled way.  It was the best I've heard bass sound in any system when he had the Super HL5 Plus.  It was more present and less dynamic with the 40.2s.  Had I not experienced the setup he had with the Super HL5 Plus, I would have loved the bass in his current setup and don't think there was anything "bad" about it, but the overall presentation was much different.

While I enjoyed them, I didn't leave wanting to replace my Super HL5 Plus speakers with the 40.2's.  The 40.2s are better in many ways, but I really enjoy my Super HL5 Plus and think the bass of the 40.2s might be too much for my listening space.  They are definitely too big physically for the space I have available, but they are beautiful and sound incredible.  If I had the space and the budget for them, they would be wonderful.