I don't have SO concerns these days and haven't been using a burner phone. Yes, that leaves the LE risk but I haven't yet heard of anyone being tracked down after the fact. Of course, that could change. When I'm on a fishing expedition, texting possible new places, I use Google Voice since I'd rather not spread my number around too much.
The other day, I was visiting a legit place in Bayside. I walked in the door and there was no one at the counter. After waiting several minutes, I finally called them. A woman promptly emerged from the back on her way to answer the call which was precisely what I had intended.
Here's the thing. While the phone was ringing, I heard my real name and number being announced. WTF? My number has always been unlisted. If I call someone and I'm not in their contacts, I should be identified as "Wireless Caller". It turned out that when I switched carriers over a year ago, this setting changed. I use Visible (Verizon's MVNO) and they don't default to "Wireless Caller". It took about five mins to fix this with customer service but still what a howler. Maybe it's time for Witness Protection.
So if you change carriers, double check how you come up on Caller ID. Or just go with a burner.