In case you go for Shimano again, the plastic tophats can be popped off and more grease smeared around inside ’em. Lots of people seem to go for XTR from Rose, however they have lightweight race seals. I thought I needed to replace mine (probably Deore, came with a Hone chainset from Merlin last year) as my non drive side was seizing, greased it up and it’s fine now! Probably won’t get beyond winter but I reckon greasing it in advance would have prolonged it’s life further.
The tension bolt thingy can very easily be overdone which will definitely kill the bearings.
Saw this about popping stainless cartridges into HTII cups: http://www.pistonheads.com/gassing/topic.asp?t=1137096