I just played a Colony game that had these contenders: Mountebank, City, Hunting Party, Golem, Philosopher's Stone and Transmute. Ghost Ship, Vault, Tribute and Fool's Gold were also available, but were ignored by both players.
Now if Philosopher's Stone is the only Potion card, there's more of an incentive to skip it, because of its opportunity cost, but this was like a perfect storm: Mountebank in a Colony game slows the game down to a crawl. PS likes this. And then there are other Potion cards which you can buy. I didn't buy a Golem, because PStones were more important to me and I didn't want to Golem into a Transmute, but the option was there.
I started Potion/Silver to my opponent's 5/2 Mountebank/-, so I was immediately behind and had some catching up to do.
My first Potion buy was a Transmute on T4 where I could have bought a PS to help deal with some Curses possibly or to trash some of my starting Estates for a Gold or two. After the Transmute I just bought a PS every time I had the Potion.
By the end of the game my PStones were roughly $7 each and I ended up with 6 Colonies to his 2.
Him: [38 cards] 8 Cities, 3 Hunting Parties, 2 Golems, 2 Mountebanks, 9 Coppers, 5 Silvers, 1 Potion, 4 Estates, 2 Colonies, 2 Curses
Me: [55 cards] 7 Hunting Parties, 3 Philosopher's Stones, 1 City, 1 Mountebank, 1 Transmute, 16 Coppers, 7 Silvers, 1 Potion, 3 Golds, 1 Province, 6 Colonies, 8 Curses
That's right, I lost the Cursing war 8-2, I only bought 1 City late in the game to his 8 and yet I prevailed due to PS playing an incredible role here (and him not buying any actual money).
My PS was played for $5.8 on average, with the most valuable PS giving me $9. PS sort of anti-synergizes with big hand sizes because it makes your PS less valuable (less cards in deck and discard, more in hand or on the table), but it was more important to me to draw it and play it anyway. Hence, the Hunting Parties.
To summarize I will stress that PS loves slow games where you can steadily build up the value of your PStones. Now, this means that you will also see your PStones less throughout the game, but this is made up for by having an almost guaranteed Colony every single time you can play one of them. Of course, the article on the front page illustrates a combo with Herbalist in which you can both buy more Philosopher's Stones and play them more often, but if that ability is lacking, a slow game is what you want.