If you are greasing the suspension regularly (original recommendation was every 2000 miles if I remember correctly), you should be able to spot split gaiters at the same time, and fix them before dirt ingress and grease loss ruins the CVs, rather than wait till MOT time. Greasing takes about 5 minutes to do all 8 nipples, 6 front and 2 rear. Front wheels on full lock, lie on ground, preferably on old piece of carpet. Easy. Other bits in the area such as ball joints need checking every 6000 miles, at every service, with the wheels jacked up.
I get the general impression from some discussions here that many Mini owners never grease their suspension. I base that mainly on the number of people with upper arm bearing problems. Those, if lubricated, are usually good for 150k miles or more. Sad, because they end up spending more money needlessly.
I do grease the front and rear suspension nipples but I never noticed that the gaitors were perished. I will be getting the gaitors, ball joints and wheel bearings replaced on monday since I think they are due for replacement (cars done 95K and havent had any major issues so far).
