Apart from the spacers supplied with the MTB version are there any other material differences between their road and mtb bottom brackets. i.e. will the mtb version used with the road spacers fit a road bike?
The only difference in the current one is the width of the sleeve in the bottom bracket. You can buy the sleeves separately or run without one, the bearings are well sealed. The older versions were different for road and Mtb versions so it will depend on how old yours is.
Ill reiterate what Welsh boy said, no problem to run without the sleeve, but make sure youre using the correct spacers as per the instructions for your shell width which may be different for MTB or Road