Kenzup,
If you want Kestrel connection, that narrows your choices dramatically. Considering the distances etc. that you are talking about, you are basically talking about the a Vec x, Leica 2800.com, a Sig 2400 BDX (not ABS, it does not connect, but has AB Elite onboard), and a Sig 3000 BDX. I will not go over the Vec x, I have only played with it briefly and does not fit my use profile for a few reasons but I fully admit I am not an expert on it. One thing you mention, about it fitting in your RF sleeve, I don't think it's that size/shape, so I'll move on past it.
The others, I have all of these RF's. I have a fairly long review on the 2400 BDX on this board you could read up on to give you an idea of what it and the BDX system offers. I also have a shorter review on the 2800 up (it was a prototype device, so not a review of the production model that I have now). I will be getting something up on the 3000 BDX just as soon as I can finish the review on the BDX scope we are testing.
Short version on all of this is they all have their strengths and weaknesses. The 3k is in many ways in it's own class because its running out of a bino....that not only changes it's utility and workflow, but it allows better ranging due to larger receptors etc. Of these three, it's been the champ for sure for me when it comes to ranging, as you would expect it to be. That said, we are talking distances farther than most people would ever shoot, though not all people....(the ELR guys for example). I'd say that if you want to consider the 3k, then it sorta stands on it 's own because it is a bino, not a CRF...giving it some unique characteristics. In reality, for it's workflow, you would want to compare it to other bino RF's. But then none of those connect to a Kestrel (or Foretrex as Sig devices will also do), the alpha models glass will be distinctly superior, and others in it's price range won't offer BDX capabilities if that matters to you.
If you are looking at the two CRF's...the 2800 and the 2400 BDX...the Leica has the glass, no doubt. The sensor positioning in relation to the reticle is also more precise than it is in the Sig and the divergence is smaller than it is on the 2400 (but not verses the 3k). So I generally find it is easier for me to get my targets with the 2800 vs the 2400, and on some targets, I think the 2800 has a little more reach than the 2400, especially in full sun (again, the 3k is a different story). And the Leica has the added benefit of an onboard compass (for automatically communicating DOF to the Kestrel), as well as integrated environmentals for standalone use (the Sig has to source these from a mobile phone either live or preloaded). Consequently, the Leica also has a significantly higher price tag to consider.
In the Sig 2400's corner, the price is much lower. The RF itself is much faster on re-ranging, the connection to the Kestrel on wakeup is much, much faster, it will also connect to the Foretrex, and the BDX integration to the scope is no gimmick. We have used it hunting and just did a precision rifle class with it to test it's utility. It's a very fast system in terms of workflow.
Both devices tend to have their quirks in terms of connectivity. You need to have the devices close together. But when they are close, now and then you will still have to re-range with all of them, and with the Sig and it's instant re-ranging, don't overrun the connection speed....but it works pretty well.
Some more of your questions:
Sig's 2400BDX seems to fit the mold but needs an adapter to attach to a tripod - correct, the 3k does have a integrated socket however
Do all the BDX series connect to the kestrel? No, only the 2400 BDX and the 3kBDX
The 2400ABS seems like over kill considering I already have ABS on the Kestrel and my phone but maybe I am missing something - No connection to anything other than a phone here, but does not really need it. AB Elite is integrated, with an integrated compass. Wind is a bit fiddly, temp drift is a reality, some only care if you are doing ELR, others don't care at all, others still, do care. If you care, the Kestrel is the best device for dealing with temp drift to my knowlege (not sure how well the temp probe on the Foretrex works).
Sig 3000BDX would cut down a piece of equipment I need to carry and the need to go back and forth from binos to rangefinder - Yes, very efficient workflow, especially if you are using a BDX scope. However, this is not Alpha glass, as the price point should indicate.
Probably more like Viper. Sig places it at Zulu 5 level, check out Robbie Denning's review of the Zulu 5's for another opinion.
I also like the idea of the BDX scopes for hunting but have no experience with them - As mentioned, we have a 4.5-14. Am currently reviewing it. So far, pretty impressive. It has limited elevation, so that is an issue for some people, but as a hunting scope for most people, it's a non issue. On my son's 270, the dots were sufficient to about 1k yards with a 100 yard zero. Glass and coatings are decent, but not top drawer. About the same or a little better than a Zeiss HD5 in our opinion so far. Tracking for us has been spot on when using it manually, but you don't get very far.
Hope that helps a bit, there is a lot more to say and consider here...these three new devices are really feature packed and quite different from each other, so please let me know if you have any other questions as, I have tried to summarize, but probably only scratched the surface. Feel free to PM me if you want to hop on the phone if that is more efficient.
