Audio Research LS-16 Mk2 vs LS-17 preamp

Rwwear, What leader am I following? I have my opinion just like you have yours! and I stated it and mine was based on having owned the LS-16mkII for 3yrs. not one week!! Just because I happened to agree with someone else doesn't mean I'm playing follow the leader!
I have had and currently have ARC systems for 25 yrs.(not that I haven't tried other products)and find their products to be of high quality and a pleasure to listen to as has been voiced by many others.(again check the reviews)
As far as ARC disliking their own products because they continuely improve upon them, that's what their name indicates "research"(duh) They're constantly researching how to make their products better! That doesn't mean you have to change every time they do.(you don't buy a new car every year because GM Ford or Chrysler or whoever comes out with a new model do you?).
I currently have the LS-25mkII and am happy with it. I didn't feel a real urge to run out and buy the LS-26 when it came out even though I know it is better( yes I heard it)
Finally, they don't change their products every year. ARC products have a minimum 3yr.run

FWIW I have an sp16 (ls 16 with phono I believe) and think it is a fantastic piece. I can enthusiastically recommend it to others.

I bought a used LS-16Mk2 on Audiogon last year, and I am consistently impressed with the dynamics, imaging and natural tonality of the unit. (It replaced a Sonic Frontiers SFL-1 with Mullard tube.) My source is a Sony SCD XA777ES which has single-ended output only. Recently I tested the single-ended SP-17 in my system, which came close to the LS-16Mk2, lacking just a little in dynamics and presence. However, the fully balanced LS-17 (which I've not heard) offers some circuit enhancements over the LS-16Mk2. I would be willing to pay around $300 more for the newer model. But either one will bring you a lot of musical pleasure.

The SP16 is NOT the same as an LS 16 with a phono preamp added! As the people at ARC will tell you, the SP16 is a lesser level preamp than the LS16 (no offense, just clarifying) in their line up.

My understanding was that the ls16 is just an sp16 minus phono stage.

So what is better about the ls16 exactly? I'd like to know because if that is the case I may have been mislead. The naming convention would certainly seem to indicate that these are the same only one has a phono. That's how it was presented to me and I had no reason to suspect otherwise.