What size base for 15mm figures?

[Gundamentalist 5.56]

I've just bought myself some 15mm SF figures from GZG for my Traveller game.

I'm new to the scale, is there a common washer size or similar that's sort of universally accepted for individual basing? I considered 20mm round slottas for a few seconds before dismissing the idea as vastly overpowering the figures, so its back to washers I guess.

[Wirelizard]

I've always found the GZG figures to have large enough integral bases to not need anything else, personally.

But then, I've always been a fan of minimalist bases - 20mm (pennies, usually) is as large as I go even with 28mm figures.

I did use 12mm washers for one batch of non-GZG 15mm figures that had tiny, tiny bases barely bigger then their feet, but none of my GZG stuff has extras bases.

[Froggy the Great]

But then, I've always been a fan of minimalist bases - 20mm (pennies, usually) is as large as I go even with 28mm figures.

Oh good, I'm not the only one.

[redzed]

Coincidentally I asked the very same question on Frothers, I'm just waiting for some € 1cent pieces to be sent to me, as they're about16mm wide.
As you live in London I expect you'll be able to get them relatively easy.