It seemes that Piotr's appeal was to the native speakers of any languages but Russian. Now I will know where to apply if I need to correct my pronunciation. :)

 I still hope to be helpful on the issues of Pskov district dialects (the region where some of my ancestors come from).

Sergei

 

 As for the quality of [ɪ], there are also significant differences between various accents of English (e.g. Australian [ɪ] is higher than in RP, and Scots [ɪ] is more centralised. The same is true of other IPA letters. The conventional symbol [ʌ] is used for rather different vowels in RP, General American, Scots, Irish English, Russian (the second weak vowel of молоко [məɫʌ'kɔ] 'milk') etc. In a very narrow transcription you can always use diacritics to pin down a particular quality or to express other niceties like the prelabialisation of the stressed /ɔ/: [...'ku̯ɔ]. How much accuracy is desirable depends on what you wish to describe.

What counts when we use [ɪ] and [ə] for the purpose of transcribing Russian is that we indicate a contrast between two different weak vowels, one of them front (and relatively high) and the other non-front. Since an immediately pretonic /i/ retains its identity as a phoneme, there is no reason why it shouldn't be rendered simply as [i] except in VERY narrow phonetic transcription, where a special IPA diacritic may be used to represent its slightly mid-centralised allophone [i ̽].

Piotr