Q. If one has the choice to daven in an outside minyan versus davening b'yechidus in a beis medrash that one has access to, which is better (as there is an inyan of davening in a closed area as well as doing in a beis medrash)?
A. Horav Shlomo Miller Shlit'a suggested that one should daven a proper and slow amida with the necessary and right kavanah beyichidus (by himself), in the beis midrash that one has access to. He should also just exit to that outside minyan, only for answering kedusha and kadish if possible.
The Rov stressed to be careful with the all conditions that were set for attending such a minyan, as described in question 2638.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller Shlit'a