guess which one will be the last to fly
Excellent point. I recall the CFI explaining to me rather forcefully that such and such plane is not to be flown unless necessary, because they lease it in and it costs them more to fly it as a result, than the rest of their fleet.
As regards Benefit in Kind
never fly it yourself
is not an issue provided you get invoiced at the same rate as outsiders.
However, the Revenue is attacking all these businesses right now. I've had to put up with several enquiries in several years - they do it just for fun, to p1ss you off. They drive £10,000 cars and don't like anybody who they see as "rich". Mine has been properly set up from the start so I have been OK so far. But it has cost thousands in the accountant's fees to deal with it, not to mention my time in drafting long responses, rebutting 5-page attacks point by point. They know that if they keep attacking you and mounting enquiries then eventually you will get fed up with it, strike some sort of a compromise deal, and close the business.
It's not worth doing unless you are buying a new plane for £250,000+VAT and want to get the £43,750 VAT back on it - then it's (arguably) worth setting up a proper business around it, rent it out, etc and pay the ongoing costs, accountancy fees, etc, invoicing yourself, etc, of running it as a company.
For a £15000 spamcan, no way.
Find a good mate or two and share it.