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?

XeTeX довольно годная штука, но будь готов к тому, что математических шрифтов с кириллицей полторы штуки и поэтому единого оформления всего текста включая формулы (как например с CM) добиться скорее всего не получится.

Тут всё зависит ещё и от того, что ты хочешь сделать, и сложности возникают отнюдь не с набором.