People of the same type with different enneagram types are drastically different. Also people with different instincts are drastically different too. I find it extremely difficult to stay interested in people with the sexual instinct last, it's like they are super dull to me. sp/so types are a struggle to even get close to, so/sp is the same. It just feels like a fake interaction. But with sexual firsts... it's great. Regardless of any other letter or classification system, if they are all different but we are both sexual firsts, it works out great.
It's almost like the enneagram number has become a fifth "letter" of the type code. I would like to think that they somehow correspond more closely. When I first saw the Ennea-types, I clearly saw five pure temperaments, plus four moderate blends, and the instinctual variants directly parallel the three areas of Inclusion, Control and Affection. However, enneagram does not allow mixing types according to the variants (any type so, any type sp, any type sx). I bet that might make more of a correlation. Like as it is, several of the types do sound a lot like the Interaction Styles (7=Get Things Going; 8=In Charge, 9=Behind the Scenes, etc), and Interaction Styles sounds like it would correspond more to the so area.
I tend to be basically 6w5, and in tests that do not give wings, have come out as 5, sometimes with strong 4. A lot of other INTP's are 5, some with either a 6 or 4 wing, and some are 9's. The difference seems that I have stronger F than others, and both 4 and 6 are very F, of course. Again, I see that APS temperament correlation as key to bridging the Enneagram and MBTI, because Enneagram does seem so similar to APS in some ways. 6 and 4 are both very Supine. 5 is more Melancholic, and I believe most INTP's temperament mix (Phlegmatic instead of Supine, plus the NT) averages out to that, or you could just say it is the stronger IT. (see next). 9 is Phlegmatic, so INTP's would figure as that type as well.
Is there a list of any kind (hopefully somewhat accurate) that shows correlation of MBTI types and Enneagram types in individuals? Seems like that should have been a thesis topic for a psych student. It would be interesting to see what the distribution is by type.
Here is my theory of how they correlate to the ancient temperaments:
Temperament Part 2: The APS and other theories and Instruments
I've kind of backed down from really pushing this for now, because of seeing many correlations with MBTI that do not seem to match (INFJ 3's, etc). However, the correlations we have been seeing do seem to stay within a certain range. Also, I make a table of another correlation, by David M. Boje ("Leadership Out of the Box", can be seen here:
Enneagram).
1 ISTJ, ENFJ, ENTJ, ISFJ (common thread: J)
2 ESFJ, ENFJ, ESFP, ENFP (common thread: EF)
3 ESTP, ENTP, ENTJ, ESTJ (common thread: ET)
4 INFJ, INFP, ENFJ, ISFP (common thread: IF, [en]F)
5 INTP, ISTP, INTJ, ISTJ (common thread: IT)
6 ISFJ, ESFJ, INFP, ENFP (common thread: EF/IF)
7 ESTP, ESFP, ENTP, ENFP (common thread: EP)
8 ENTJ, ESTJ, ENTP, ESTP (common thread: ET)
9 ISFP, INFP, ISFJ, ESTP (common thread: I[e]S[n]F[t]P[j]: all-around moderate)
These are big on the E/I + T/F groups (which I call "social image" groups), and close to what my correlation would suggest; even matching the Interaction Styles on the S side. There is one "sociability" group: EP, for 7.
Type 2s and 7s are the most common amongst ENFPs.
ENFP 2 is mentioned in the list above, but I think that's the only place I have ever seen it. 2 is almost always made out to be Fe types. ENFP's seem to be big on 6w7, 7w6, maybe some 6w5, 4w3 of course, and there is even some 7w8.