I much prefer UA E+ over LH Y. As for upgrades on LH, its much more difficult as you need to get a paper certificate, it won't cover the entire trip (just the one leg), and won't happen until the day of. In addition, I think you can only upgrade Y/B fares on LH and still need 30k miles. On UA you at least have a chance of confirming/clearing your upgrade in advance and can do it with a lower fare bucket.