Hobo --
Not sure you'd go really wrong with either, but not sure I agree completely with widebody...I have used an E-Trac fairly extensively, and while there are a few things I like better about it, there are a few things I like better about my Explorer, too -- and bottom line to me is, the E does not get deeper, nor separate targets better, in my experience. Since you are used to an Explorer already, you might like the SE better, as it has some nice improvements over your XS (particularly, the pinpoint feature). You would like the E-Trac also, and it would feel pretty familiar to you overall (as I truly feel it's just an Explorer at its core, with some changes -- despite the fact that some will vehemently disagree with that statement). But, bottom line, I don't personally see that much advantage for an experienced Explorer user such that it would be a major improvement for them to switch to an E-Trac.
Just my two cents worth...
Steve