Those may well be the ones I read about somewhere. If they are indeed soft or likely to become a problem at some point then best to change them to something better when in there. It is certainly something I will keep in mind for the first time I have cause to open mine up and changing them to something you can get a good purchase on when needs must is no bad thing.I have not heard about the outer case screws and I think most of these are hex machine screws so you can get a good purchase on them? I think some regular maintenance is required anyway so by my thinking, if they are not left in situ for years without even being removed maybe you could have a problem. However, I have heard about the screws that hold the internal motor in place seizing. These are not hex and apparently have heads made of a soft cheese like substance. You need to be able to remove these if and when you need to replace the blue gear - I think these are candidates for replacement if you are likely to not perform regular maintenance? No 1st hand experience mind you. I do think the needle bearing is noisy on my unit so I have a replacement blue gear, may get around to fitting at the weekend...
All the best,
AJ