I have recently come round to the idea that Polish Club isn't greatly superior to Precision, if at all. To compare the two systems, it is probably best to compare variations with a lot in common. So, for PC I will work on 12-14 bal with 4♦s being opened 1♦, and for Precision I shall use a 4 card diamond suit (1♦:1major, 1NT showing 11-13), a 12-15 NT, and no Precision 2D opener.
[Firstly, a hobby horse...I don't think Precision 2♦ should ever be used. If you are that keen on having an opening bid for these hands then open them 2♥, this puts a lot more pressure on the opps and frees up the very useful 2♦ opening].
Precision gains on the hands that are opened 1♦, 1♥ and 1♠ in both systems, because they are much more limited.
Precision also gains when 1♣ is opened, assuming there is no interference (a big assumption I know). Relays should be used to maximise the gains.
My suggested wide-ranging 1NT opener isn't great, but with the use of Keri, and a small modification allowing you to play 3C when responder has 5 opposite a minimum (which then must deny 4 diamonds) will minimise this loss.
I'm not sure how well PC handles weak NTs and 4441s in an uncontested auction, and as I am in the middle of exam period

Right, now onto the big issue of interference over 1♣ openers.
Yes, a Precision 1♣ does ask for preemption more than PC, as 2nd seat cannot be sure whose hand it is when a PC is opened. But if he does interfere, responder doesn't have the guarantee that partner is strong, which makes things a lot harder for the PC pair.
Now change the above slightly. Let us have a pass on your right, followed by your opening a multi-club on your huge hand. RHO can cause you far more problems than he ever could over a strong club, because your partner cannot rely on your having strength. The ambiguous nature of the Polish Club has rebounded on its users. Surely this problem is so severe as to make multi-clubs totally unsound except in 1st seat?