I have both the Leica 2700b and the Sig 2400 BDX. I put up a review on the 2700 on another board, but suffice it to say, it ranges very well and has outstanding glass, definitely best glass in it's class if that matters to you.
The 2400 BDX, which I am currently reviewing, also ranges very well, though on non-reflective targets, in my experience, the 2700 reaches just a bit further, but for both, we are talking over a mile on trees here. Likewise on glass, the 2700 is better.
However, when it comes to ballistic solutions, the 2400 offers the capability of connecting to a Kestrel with AB. Whereas the Leica (and all BDX RF's) are limited to 800 to 1k yards (depending on configuration) for their ballistic solution when used stand alone, when you pair the 2400 BDX to the Kestrel, you get a solution for as far as you can range. Of course, you can use the Leica manually with the Kestrel once you get past it's 1k solution limit, but the connection to a Kestrel is much faster and surer.
The BDX connection is, thus far, stable and excellent, and the RF itself is very fast.
When using them stand alone, both will allow you to load a custom curve (unlike pre 2700 Leicas), which really comes into it's own as the distances stretch. If you are looking for a top shelf solution for under 1k, you might have a look at these two.
However, if you are not interested in having a ballistic solution in your RF, then the Sig Kilos and the Leica 2400 would save you some coin, though I think the 2200 BDX is probably in that same price class, which would give you the ballistic option, though not the Kestrel connection.
HTH!
