Line Magnetic 219ia vs. 518ia

I have been interested in the difference between these 2 integrated amplifiers from Line Magnetic for a while now, and thought that some members might be as well. Given the difference in their size and price, and the very enthusiastic review of the 518ia by Herb Reichert in Stereophile, I was hoping that the difference would be minimal. That was not the case
I went to audition both amps this afternoon at Arizona Hi Fi on a pair of DeVore 0/92 speakers with  Luxman CD player and Nordost Odin interconnects (!). Both were fully broken in. First the less expensive 518ia. Sounded good, not great. A little harsh almost on some loud sax breaks, but then again, I never heard these speakers before. PRAT, which was highly touted in the Stereophile review didn't seem any better or worse to me than what I get from my Audio Note Kit1.  Listened to Jazz, Cream, Jethro Tull and Squeeze.
Next up was the 219ia. Instant difference, no need to lean forward and squint. Very obvious that there were 300bs in the circuit. Smoother, much more layered, detailed and refined. A real wow moment. Listened to all of the same again and was very rewarded.
I love my Audio Note but have been considering a change because besides my horns, I have small inefficient monitors that I would like to use occasionally. Both amps had very good bass reproduction due to the 845 tubes. The reason I felt the need to write about this is that in one of the major reviews of the 219ia, the reviewer compares the two and seems to say that the difference isn't much and that he'd be happy with either. Not me. There is a very big difference.
The dealer also had a new amp not on their website, the 508ia which uses 300bs in front of 805 tubes and some 6sn7s I think. I didn't have time to hear it today and the salesman was tired of lifting!
As an aside, I finally got to audition the Sugden A21 class A integrated on his recommendation, and that its a great little amp. As good as the 219ia? No, not quite as colorful and a little bit drier on the top end, but excellent musical sound in most ways and a great value.
I thought that I would want to keep my Audio Note no matter what else I might buy, but if I buy the 219ia, I can let the Audio Note go. It's a great amp.   
Roxy mentioned that he has a 2nd pair of speakers that are less efficient so the higher powered LM amplifier would be an advantage.  In terms of more efficient and sensitive speakers the comparison of LM 845  and AN Kit 300b becomes very compelling. You can not lose with either of these choices. 
Yes Charles, I have a pair of Celestion sl6si and a pair of Ceslestion Kingston, and who knows, there may well be others in the future . I want to be able to hook them up occasionally, and they are sealed box 86db efficiency. I've already tried the Audio Note with them, and it just doesn't cut it. They need more power.
Yes, the Audio Note has proved to be all that I hoped for and more. Like Charles, I still shake my head as I read comments about "wimpy" 300b amps. It really is not the case if you use the right speakers. Everything about the presentation is so far superior to any solid state I have ever heard that it makes them sound like the equivalent of a pixilated photograph.  
Given that you want to drive 86 db speakers then the Line Magnetic 508 (45 watt 805 tubed SET) could be the ticket Roxy my 300b SET has elevated my listening involvement to an entirely different level as you attest to with your similar experience.
@roxy54 I totally agree with you and always agree with Charles lol, I find a good tube amp with a beefy power supply can drive far more speakers than people realize. My own speakers are either 89 or 90 db, I forget exactly, and I drive them spectacularly well with my 17 watt amp. I’ve thrown a variety of amps on them over the years, various loaners from Deja Vu including a PP 45 amp that was pushing maybe 5 watts and drove my speakers just fine! As always its quality not quantity and the first watt is always the best watt.