Sorry for the delay in replying - was busy getting the car ready for the last round of Slough's Winter Series...
The OS 28 is supposed to be a bit of an animal....personally I'd prefer a decent .21 over a .28. Am currently running an OS Speed in mine but also have a 7 port Sirio CL7B STI which is also very good...
If you want to go back to the standard Kyosho hub/knuckle setup I still have some of the stock (cast) knuckles if you want them (as I run the CNC ones which were released as an upgrade when the long chassis conversion came out a while ago). I can post them to you if you aren't able to get somewhere where I am racing...if you want them, just PM me your address..
If you aren't busy Sunday - I'll be racing at Dartford if you want to come along and have a chat etc - providing the people that run the club are happy - you can have a drive of my ST-RR at the end of the meeting and see how you like the setup. My setup is loosely based on Mike Craddock's setup - Mike is also racing at Dartford on Sunday (with buggy) if you have any questions etc...
CheerS!
M