It all depends what you mean by p4p. It's purley achievements then that would be a slightly different list or order to the best boxers.
To me, P4P takes everything into account. Ability, achievements, resumé, longevity, everything. If it was just on achievements then Ricky Burns would probably be top 2 or 3 P4P in the UK. And no disrespect to Burns, just using him as an example of somebody who's achieved loads but isn't in the discussion of who's the best.
Joshua Fury Warrington Saunders Callum Smith Not in order but those five instantly spring to mind. All undefeated, all World champions or ex World Champions, all in their prime. I don't like Saunders, I don't like how his career has gone and I think he's a bit of a waster on the whole, but he's done enough to get into the top five if you ask me. Josh Taylor is very close to getting in there and, a year ago, Lee Selby and Carl Frampton would probably have been in there too.
Top 5 PfP in Britain Résumé and Skill In a rough order but completely interchangeable 1. Warrington Selby and Frampton are damn good wins and as unpopular as it would be he's actually 6 on my world wide pfp, his skill set is very underrated 2. Joshua He's not my favourite but he's got a damn good résumé and is technically improving in each fight Granted his best wins are both old and one was green, but Parker is good win as well 3. Fury Should've beat Wilder, has a win over a better Klitschko than Joshua but he isn't an actual champ (lineal isn't really recognised as much now though I think it and the rest of his résumé isn't as good, but he makes up for with skill, it's split ends between them 2 4. Josh Taylor Few half decent wins, but his Skills put him here for me, very gifted fighter and if he wins his next fight then I'll have no questions about him being here 5. Callum Smith Massive for his weight, probably beats everyone at SMW and his a good stand out win against Groves This time Last year I would've had Frampton, Saunders and Groves on here as well I feel Saunders is the best UK fighter in the world pfp when he shows up at his best, but he rarely does and been managed appallingly