i know plenty of dudes who run the 110 shimano; i run a 107. they both work fine. your chainline won't be perfect, but it'll work.

This is absolute truth. People need to get over their fears of unsealed bottom brackets.

It will be hard for me. Less than 9mo old and one rainy century ride killed it.

Bad luck? I've put unsealed BBs through worse than that with zero issues. I've never tested my 75 cranks and BB like that though. I try to not to ride that bike in the rain, though I've been caught in a few downpours and snowstorms. But so far two winters with no overhaul or adjustments and its still smooth with clean-looking grease.

Yeah it could be bad luck. Others have suggested a poor install, but the LBS that did it does good work and the monthly or so times I had the chain off the bike there was no play in crank, perfect smoothness. When it was opened up the grease was in like new looking condition, but there was (clean, dirt free) water inside. Had 5k mi on it.
Is it worth the gamble to drop $100 again? Maybe. Will I then become ultra adverse to rain and therefore give me too many excuses to not ride if there is potential for rain? Likely. Will I notice a difference between the Sugino 75 and the Shimano UN54? Probably not. Yeah the Sugino was ultra smooth, I thought I could feel that - definitely could when the bike was on a stand, but under load? Even better was the near perfect centering of chainring to axis of rotation, no chain slack spots. Does the UN54 not feel smooth? No.
Believe me I am tempted to go back.
Al