[KaVir]

If the boxes are obligatory, what would you initialise them to? The muds listing themselves as "pay to play" could have the first box automatically clicked, but for the other muds you'd have to do one of the following:

1. Manually go through each listing (not feasible),
2. Default them to one of the options (resulting in incorrect listings), or:
3. Leave them blank until the listing is updated.

If you go for the third option, then those muds that really don't want to select an option will just avoid updating their listings, which doesn't really benefit anyone.

Don't forget though, if muds choose not to select any of the options, then it just means they'll show up on fewer searches. If you're running a pay-for-perks mud, the people looking for non-payment muds aren't going to find you with a search even if you don't click any of the boxes - but if you don't click any boxes, the players who prefer pay-for-perks muds won't find you either.

The last three options are mutually exclusive, but I could see some people trying to select multiple options just to appear on more searches. Furthermore, a pay-to-play mud which has no additional costs would presumably click the first and last options, but the last one is rather misleading (particularly if people are doing a search for non-payment muds).

I think perhaps they might be as radio buttons after all...it's a bit unfair on the pay-to-play muds perhaps, but their listings aren't really going to be affected by this change anyway, and they'd still have the text area if they wanted to elaborate on their payment model.