That's a nice block and a really good deal for someone who wants an off-center block that will drop in place of a 109. Nice BMS off-center blocks are very rare these days.
Rollie you just keep coming up with all kinds of cool Stage 2 parts!! Good seller BTW I bought an on-center block off him a few years ago very positive experience I am still looking for a 3.59 or 3.625 wide-journal crank, BMS or off-shore brand if you come across one.
That is a Stage 1 off-center block which is essentially the same casting as the S2. The differences are in how it was machined. The bulkheads in that block can be milled out and machined for a 4-bolt main cap or you can just put a 14-bolt girdle on it. Either-way it is a way stronger block than the 109. I would run it like it is unless you are planning a 1200+hp build which is more than the off-shore cranks or BMS cranks will withstand. And if you are planning an all out build I would start with an on-center to begin with.