If your interest is primarily in route-building and not the built-in routes, then unquestionably T:ANE Service Pack 2 will be the way to go.
It's in public beta right now and shouldn't be too far away for roll-out to all.
There's a good deal available for the current versions purchase (T:ANE SP1 HF4) right now (66% Off - ends 18th April, so be quick!)