We had some PHP flushable ones, but in the small print it does say not suitable for all systems/pipes, or words to that effect. And sure enough, they aren't suitable for all systems/pipes, which we found out when our next door neighbour called someone out because the drain between our properties appeared to be blocked. It was blocked with liners and we were lucky not to have to pay for it all. But our neighbours had called him and had insurance so didn't pay any call out charge, and the guy was happy to slip our £20 note into his back pocket and say nothing about it being our fault!
I still use paper liners but now just sluice any poo that doesn't drop off easily, then wash and reuse them til they get holes - they last quite a few washes and get softer each time