Just a few comments:
On a cold/rainy day, the E lounge balcony is closed. That accounts for at least 50% of all days in ZRH
When the balcony is closed, the lounge is still nice, but not that great anymore (it's lacking the SEN whisky bar, after all
)
Food-wise, it can be OK or "quite meh", depending on daily offers. Not worse than various SEN lounges elsewhere, in fact probably better, but they're holding the bar pretty low for that.
Not really great choice of drinks, but again, depends what's your bar.
It can be very crowded just before boarding of the many simultaniously departing LX flights (especially around lunch/late evening)
Shower wait time can be very long (experienced up to 2hrs!)
Last but not least, you've to pass through immigration (which can be fast, if the automatic gates are working, or tiresome slow if not and staff isn't properly available) to and from the E gates when connecting within Schengen, so heading to E gates on less than 2hrs layover in ZRH is generally not really a good idea.