This is a two-part question; I hope that's allowable. I'm aware that an unstressed о is usually reduced, though there are some exceptions -- specifically in borrowed words, such as стерео or радио. All the examples I was able to find, however, had the о in question at the end of the word. I'm interested in how it's treated in a pretonic position (i.e. before a stressed syllable). For example, маоизм: Is that [mɐɐˈizm], [mɐoˈizm] or perhaps even [mɐʊˈizm]? How about Маометто (Italian; stress on the penult)? Is it something that is up to each individual speaker to decide, when to pronounce an unstressed "foreign" о and when to reduce it?
The second part of my question is about whether or not there is a glottal stop in between two reduced vowels that produce identical sounds. For example, сообщить is reduced to [sɐɐpˈɕːitʲ]; is there a glottal stop between the two /ɐ/s, or is it essentially just one /ɐ/ sound held longer than a typical /ɐ/?