The connection at Twickenham between the Hounslow and the Kingston services is excellent, just 6-8 minutes towards Kingston and 5 minutes towards Hounslow. This means the journey can be completed in 30 minutes, and is much better than the 45-50 minutes the bus takes (of course not when it comes to the 2tph frequency!)
In contrast, the connection between Reading and Kingston services at Twickenham is appalling. The train from Reading arrives just after the Kingston train departs and the train to Reading leaves just after the Kingston train arrives meaning a 30 minute wait in either direction.
but very satisfying when it all comes together and you can watch it all operate.