Is it disrespectful to do research in two labs? Context: Undergraduate computer engineering student in the US looking at attending graduate school in two years. I’m trying to figure out which research topics interest me—hopefully to find one to pursue in graduate school. I’ve only done one semester of research so far and I’m switching out of that lab because I didn’t enjoy it (unhelpful PI and graduate assistants). 

Question: Is it seen as disrespectful to be in two different labs at once when trying to figure out a research topic to pursue? If not, should I be aware of any other conflicts when working for two labs?

I’m concerned primary about how this will be viewed by the professors, not the ethics of being in two labs (the research topics are pretty different).
We had an undergraduate in our group quit abruptly at the end of the quarter, saying he liked the research better in the other lab he was working for. This is fine, everyone knows some people won't work out for whatever reason.

However, this was the first time my PI had heard he was "two-timing" us, and yes, she was pretty upset. 

I do not think it's per se disrespectful to work in two labs at once, but it is certainly rude to hide that fact from one or both groups. That said, if you tell two PIs that you're working in two labs to figure out what you like better, they may be less inclined to help/mentor you because they know there's a big chance you'll drop their lab pretty quickly because you can fall back on the other lab you like more. 

I don't recommend this course of action, but as long as you're transparent with both labs, I would not say it is wrong of you to attempt it.