If anyone is looking around and wants some input on these, we recently had all of them in our hands.
We use Carlson SurvCE.
The Tesla has a big screen, but Carlson does not seem optimized to utilize that, so that feature was actually a liability, adding to the weight. The mounting hardware supplied to us by Ram was overly complex and heavy as well. The final nail in the Tesla's return box is the lack of a physical keyboard. We thought we could live without it. Perhaps other's pace allows for the extra moments needed for the onscreen keyboard, but mine does not.
The FC2500 is about a year old. The plastic case is already starting to show stress, and the keyboard is starting to stick. The implementation of SurvCE on this platform is excellent, and I expect that the FC2600 is no different. It also has a caps lock key. This wouldn't seem like a big deal, but it turns out that it matters a lot.
The Surveyor+'s build quality is impressive. It is lighter than the others, even with both batteries. Yet, it feels tougher and stronger. The keyboard feels good, but we have only had it a couple of weeks, so quality is untested.
Carlson still seems to be built with WindowsCE in mind, but works well on Windows Mobile. Version 3.0 seems identical to 2.62, and works perfectly so far.
The FC2500 has been replaced by the FC2600 in the Topcon lineup,but they don't look much different. The keyboard and interface might be different.
I believe that the FC2600 uses a different OS than the FC2500 because the FC2600 will run Magnet and the FC2500 will not.
> I believe that the FC2600 uses a different OS than the FC2500 because the FC2600 will run Magnet and the FC2500 will not.
I believe you are correct. And, at this time at least, I don't believe that the FC2600 is supported by Carlson.
I use the mesa and CE 3.0. Seems fine to me.