From the INTP perspective:
ENTJ:
Good: Watching them in action is like watching a butt-kicking version of myself - someone who actually gets stuff done. They kick butt and take names. I sectretly wish I could do more of that.
Bad: They dive into things too quickly. They need to do more in-depth analysis on the front side before jumping into the pool.
ENTP:
Good: They appear to be so smooth with people, so very likable. They claim they aren't good with people, but they really are. Very capable of whatever they undertake.
Bad: They often need to "tie up" a lot of their loose ends and get organized. They never know where documents are at, it's hard to get anything from them or out of them.
INTJ:
Good: Very steady, consistent, hard-working people. Very determined and they just keep chipping away and making progress. In the story of the tortoise and the hare, INTP's are often the hares and INTJ's are the tortoises. I mean that in the best of ways. Not saying INTJ's are "slow" at all. Just saying that INTP's are "all over the place", jumping around from project to project, taking a nap, resting, falling behind, while the INTJ's just keep plugging along and sometimes end up way ahead of us.
Bad: They need to realize that there are other ways of doing things. If something is not within their little "master plan" or circle of thoughts, they think it's stupid. And this just isn't true.
INTP:
Good: Able to see things from various perspectives, to hold a sort of panoramic view of things. Provide solutions.
Bad: Not very action-oriented, able to become very lazy if they allow themselves. Opposite problem of ENTJ's - instead of diving right in, we sometimes overanalyze and never end up jumping in the pool at all.