To be completely honest, for (really great!) SD card mod like yours, I would preffer to have a magnet glued to N900's inside case, close to sensor and use a pair of scripts for completely safe mounting and unmounting of everything SD (and for those that need it, create a fancy shortcuts or QB widget for it).

This kickstand thing seems too random for me, I wouldn't be sure that it's reliable enough (aka: it won't open accidentally). In fact, I'm using exactly this - glued magnet - that allow me to remove cover whenever I want and pair of scripts to shuffle SD card mounting and swap between SD/eMMC, when need arise.

Frankly, using such setup I don't see removing cover to access SD slot as any hassle, but, our needs may be different, and your way of executing this mod is very professional (from outside, it looks like it was designed this way all the way from factory), so kudos for that

/Estel

// Edit
What would see *very* useful, would be a way like that to shuffle SIM cards, without removing battery. Won't happen though, I guess.