After waiting a while, I finally got my hands on a build platform 2. I’ve had a chance to use it for a little bit, so I thought I would post my thoughts on the off chance someone might find it useful.
Overall, my impressions are positive, but it is not a panacea. Build platform 2 presents you with a quandary: It makes removing prints from the build plate far, far easier, but you trade that for a much worse job of cleaning it whenever you change resin.
Build platform 2 comes in two pieces. One piece is most of the item - it’s more or less the same shape as build platform 1, but it is not intended to be used alone. The other piece is a thin piece of sheet metal bent to form two handles that magnetically attaches to the first piece to form the complete unit. Since it’s sheet metal, you can bend it, and that is what makes it much easier (essentially trivial) to pop even the most firmly secured prints right off.
The problem is that if you change resin, you have to take the two pieces apart and clean each one individually. And that’s kind of a pain. In particular, the sheet metal piece has part of it that is bent back on itself to form a pair of “lips” that fit into grooves on the main part as an alignment aid. The resulting “tube” is not sealed, so resin gets in there. It also gets into the cranny at the edge of the lip. You’re just not going to be able to get all the resin out of there. I have only printed with black resin so far, so I don’t know whether I can clean it well enough to not contaminate white too badly.
Of course, this is only necessary when you change resin, which naturally suggests an obvious, albeit ridiculously expensive solution. Besides, I don’t have a good way to store dirty build platforms, though I’m sure one could print something suitable.
In the end, I’ve decided I am going to use platform 2 for resins that are difficult to remove, like black and white and perhaps tough 2k, and for prints made directly on the build plate (that is, without a raft). I will probably continue to use BP 1 for clear and durable, as those are easier to get off anyway and probably more sensitive to contamination.