[name_f]Mireille[/name_f] is absolutely stunning! I would pronounce it mee-RAY, though I have taken [name_f]French[/name_f] classes since middle school so that definitely helps.
[name_f][/name_f]You will definitely encounter people, especially in the US, who can’t pronounce it correctly – but a simple clarification is all it takes! If you love [name_f]Mireille[/name_f], I say go for it!