IMO, Laurin is the best name in Aftermarket cabs...My dad has one on his L2900 and its been a great cab.
That being said...In today's age of factory cabbed machines, I dont see how its worth it. The price to get an aftermarket cab is...as been mentioned, equal to, if not MORE then the factory cab version. with that you still have the "open station" interior and no A/C.
Secondly, when it comes time for resale, with an aftermarket cab you'll get almost open station value...because for a little more then "Open Station Value" you can be into a factory cabbed model.
You're better off trading in and up to a Factory Cab machine..