Get an Oyster card and you can go anywhere quickly and easily, why restrict your search, HSG is around Euston I believe and will suit your needs, plenty of good reviews if you look.
Thanks for replying. I live in central London, and have reviewed HSG relatively recently.
In this instance I’m going to be in the Chiswick / Turnham Green area, and fancy a punt in between meetings.
If full on PSE not possible I’ll settle for a more vanilla encounter if anyone’s able to recommend someone.
Will also search myself but it always nice to go with a recommendation. Thanks.