After two years of quite intense, but mosty "city and light terrain" use of TwoNav Sportiva I can point out its weak points.
1. Software
- if you remove batteries unexpectedly it can cause complete loss of system files and return to pure Win CE (complete loss of TwoNav system - which hurts if you don't have notebook)!
2. Hardware
(a) rear cover plastic lock was broken (as an effect of changing batteries quite often)
(b) green cover (made of gum) came unglued (close to right button and - later on - on whole right hand side) - this problem is somehow similar to my previous Garmin eTrex Vista HCx unit.
and (c) - pure speculation - as for now I use bike holder succesfully (it is perfect), but every time I demount it, I have doubt if the plastic wouldn't be broken...-
Anyway, it's great unit, but - in comparison to Garmin - IMO it is more gentle and more vurnerable to harsh conditions...
What about your experiences with TwoNav?