Never felt I had any trouble with silicone tips to be honest, so I don't feel the need to find or try any foam tips 🤔
Most people don't have issues with the silicone tips...until...
I bought my wife and I an entry-level set of IEM's to wear while riding, from MEE Audio. My wife had an inexpensive set of old-style in-ear 'earphones' (the $20 variety) and complained about how bad they sound and how uncomfortable they were. At first, she was blaming the cheap-o silicone tips that come with the cheap-o earphones.
I put on the triple-flange silicone tips, put them into my ear canals and loved 'em. My wife was apprehensive at first, until we were rolling down the road, listening to some tunes, and was able to also have a conversation without the constant "Huh? Say again?" issue.
The foam tips are probably the ultimate in isolation...unless you put down the $$$ for the custom fit silicone tips.
Which I'm considering... 🎧