| Just be aware that the replacement cylinders look sexier and have a lighter clutch action, but this is because they have a bigger bore. Because they have a bigger bore and you're only pumping a given volume from your master cylinder, the slave will only move through a shorter stroke and won't push your clutch plates so far apart.
This is usually OK (they wouldn't sell many if they didn't work would they) but it can make them fussy little boogers to bleed | 
Jools
Threaded Mode