Peter
My challenges with the soil blockers was actually getting uniform blocks out – no doubt due to getting the moisture content slightly wrong: the 4 blocker was reasonably OK, but I simply couldn’t get the 20 block mini-blocker to work effectively.
The other question is finding suitable trays to store them in: I started out putting them in tupperware boxes ax that is what I had to hand, but they were a bit of a pain to get out of those. If I were Blackberry Lane, I would be trying to find good soil block trays as well as a tray for mixing the mix on and pressing the block down on. Yes, some will knock their own up, but I would certainly buy a reliable set of 4 trays on which you could store 40 – 60 two inch blocks each, not to mention a suitable tray to mix the block mix on and make the blocks from.
Like all these things, some hit on perfection immediately, whilst others of us have to fail a bit first before we find a way which works.