Do you think conclusively that the Aneros model determines your session experience?

I don't think the model is the only factor. Sometimes you have to be the right kind of horny to have a session at all. Other than that, I still go through phases of preferring one model over another. Or a model that has been producing relative duds for months suddenly starts performing amazingly.
I think it varies too with re-wiring and random changes in sensitivity to certain types of stimulation.
I'm a fan of trying many different models, since it can break you out of certain patterns of expectation. I like to think the different models I've used have each taught me something.

yes actually i find that the DeVice works better for me than any other model i have tried so far it seems to hit all the right spots and its thicker toward the base which adds the intensity i neeed for long sessions

this might sound crazy to others but IMHO you have to read your body as to what kind of stimulation you need.I can read what type of stim my body needs/wants and choose the right model ALMOST right every time.
Sadly not always but i reckon 95% of the time.
Sometime girth is a must other times not wanted at all sometime more aggressive is needed sometime not.

I am sure the model for each person is a very individual thing too to get the right massage at the right time.

I find that all devices work on me, no matter which one i choose. But what i find is that if i choose one that the most comfortable with it leads to better sessions.

"Conclusively" is the tough sell for me on this topic. Being a anal-play junkie I enjoy a wide variety of sessions and eschew a "carbon copy existence" so, my sample size is large. Aside from my Eupho-classic, Helix-classic and recently Progasm-ICE sessions, most sessions they are poorly controlled and suffer from a lack of repeatability. The prep and lead-in for each of those toys is unique and I tend to repeat it over the long term.

For other tools I am 'casual' and 'experimental' during a session and enjoy the wide variation in sensations offered by a large toybox and repertoire of erotic activities. Certainly though my mood, going into any session is the most important factor in the outcomes.

I can however say, "Yes, for Eupho-c, Helix-c and Progasm-ICE sessions." With each of those tools I tend to follow a familiar path and the outcomes ("build of pleasure" and eventual orgsasm) are somewhat unique and repeatable for each model; however, it's more influenced by my own doing and response to what I'm receiving from the "body-toy" combination. I do restrict the use of those three Aneros models to sessions when I've craved an intense orgasmic response.

Do you think conclusively that the Aneros model determines your session experience? Or, to put it another way, can you blame a poor performance on your tools?IMHO, NO! The Aneros experience is so predominantly a mental exercise that ultimately you can achieve the same effects without use of an Aneros or any other device. The numerous Anerosless reports attest to this phenomenon. Aneros massagers are wonderfully designed tools to provide gentle, therapeutic prostate massage. The "experience" (feelings, sensations, emotional states) one derives beyond the actual physical manipulation is highly variable for each individual. It is pointless to blame (or credit) a piece of plastic for the experience one creates in his own mind.
Good Vibes to You !