Nope! There have been some episodes I wish I skipped in Season 6. I've been enjoying all of Season 7 so far.
EDIT: I do try to watch every episode so I know what's going on. My curiosity will kill me otherwise. I also rather like the way many characters are voiced, and there are so many terribly cute little animations that often make up for an episode.
No, I've never skipped an episode. My general opinion is that to do so is to miss out, because even if the episode doesn't end up being a favorite of mine, watching it adds to my depth of knowledge of the world. Plus, sometimes an "ok" episode will have a single moment that more than makes it worth the viewing.
No. Even if I dislike the synopsis/preview of a episode I will still watch it so I can get a full opinion on that episode. The Saddle Row Review is one of the best examples for a episode I thought was going to be boring and uninteresting after reading the synopsis. The preview didn't help. However, The episode ended up being my favourite for the season and inside my top 5 episodes of the show.
I have skipped an MLP episode twice before. I skipped the episode Sisterhooves Social and Hearths Warming Eve because the site that I was watching MLP FiM on had the link to them in the dub of another language. I kept continuing watching the episodes in English until I finally found an English dub of Sisterhooves Social and Hearths Warming Eve, I watched them then.
The only MLP episode I skipped was 28 pranks later, mainly because the premise of the story was completely forgettable and just pure filler. I remember some people told me it wasn't unfair to talk about an episode like that, but we're talking about an episode about Rainbow Dash pranking to everyone until she gets pranked.
Spoilers: she gets pranked.
To be fair, it's really hard to find a great episode in Season 6. I can think of… three? Maybe four?
Cheese Sandwich has a great voice actor but his story was so predictable the fandom practically wrote the script 4 years ago. (The male party pony teams up with Pinkie Pie the female party pony and they marry in epilogue? Gee. Wow.)