There's no issues. Russia doesn't restrict tourist visas because someone is British. Unless you have a criminal record plus a few other categories of general exclusion, like owning up to being a spy! the issuance of a visa is academic. It's just a faff to have to go their visa processing centre in a UK city of your choice where they have a visa processing centre because they don't do postal visa applications any more.
The UK started it by requiring all Russians to go to a British Embassy or Consulate in person to get their visa to come to the UK, so Russia just retaliated in kind.
I just went through the same process to get a China visa for an upcoming trip, and apart from their special way of administrative efficiency (queue up three times for each different bit of the process instead of queue up once and whoever you see does everything all in one go) it was a fairly painless process. I took the opportunity to go and see a West End theatre show matinee while I was in London so it wasn't a day out just for the visa.
