Rubies from any location, regardless of whether they are from Burma or Madagascar, will vary more significantly in price due to color than any other factor. Functionally speaking the biggest factor that varies the price is treatment of rubies, but the reason they are treated is to improve color and possibly clarity. For example:
R11949 is a Burmese ruby, however it is priced at less than half of the Mozambique ruby due to the fact it was treated. Now if we look at the prices between these two sources with all the factors equal:
The total price shows a price difference of around $500, the per carat price is a much better indicator of relative quality, since a few points can mean a large price difference.
The actual difference between the two per carat is a value of $285 dollars, out of thousands of dollars. Even at this high level of quality, there are actually Mozambique rubies priced higher than this Burmese ruby.
In this case the Mozambique ruby is nearly double the Burmese ruby despite both being treated. Most of the time pricing depends on the quality of the individual ruby and other factors like issues with travelling between countries at international customs, individual sellers, ruby suppliers, overall durability due to natural fractures, and so on. There are a number of factors beyond quality that can increase the price for the exact same ruby, though every seller will highlight color, then clarity, specifically in that order when pricing the ruby.
While the prices do vary between rubies of different qualities, it is also true that many sellers in the trade put a premium on Burmese rubies. Especially for pieces valuable enough to go to auction. None of the top rubies will be from anywhere but Myanmar and maybe Sri Lanka (formerly Ceylon), partially because nearly every other ruby mine did not start production until the late 1900s. For the vast majority of rubies that do not make it to the auction houses, this is less glaring and more of an issue of taste.
Burmese rubies might be the historical standard, but they have a distinct appearance versus Mozambique rubies. Rule of thumb is marble-hosted rubies (like the ones from Burma) with especially low amounts of iron have a soft, diffused red due to fluorescence. Basalt-hosted rubies (like the ones from Mozambique) with higher amounts of iron inhibiting the fluorescence will be clearer and sharper, the red often appearing slightly darker due to lack of fluorescence.
In these examples the oval Burmese ruby clearly has a softer appearance than the round Mozambique ruby, but both are excellent rubies that anyone would fall in love with.