What makes you think the problems you're having will be resolved with an updated Destinator engine?
I've seen and used v7 and as far as I'm concerned it's a step backwards. The engine is a real resource hog and the map display lags about 5 seconds behind the cars real position.
I'm now using Sygic Drive, embedded in CF. The routing engine may not be the best (IMO only TomTom really works well) but as far as ease of use and features go (varying distances on POIs etc) it's the wasps ankles.