rule

I have an HP iPAQ PDA that also has dome buttons and can emulate the Game Boy or NES, as well as play native games (Chuzzle, Bejeweled, Solitaire, Freecell, Kevtris, SimCity 2000). Mine just barely lacks the RAM to allocate a 4MB block for a WAD (supplying a smaller WAD doesn't help) so I can't play Chocolate DOOM. Maybe a repartitioning hack (allowing installation to SD) or one that deletes system programs (such as Calculator, Pocket Word or IE) could help? (The "storage" is a flexible RAMdisk, and running the battery down or just unplugging the charger when a key is pressed down erases everything in it, the system then reinstalls from ROM and all but the SD contents is lost. At least with a third-party registry editor, I can restore settings in minutes. So yeah, freeing some of the 16MB storage could yield enough RAM.)

Anyways, as LGR says about his (pretty much the same as mine but with built-in Wi-Fi that doesn't need an SDIO card), the buttons just suck. But it's mostly due to poor layout (thumbs too close, OK key protruding from the D-pad) and lack of rollover (only pressing the leftmost and rightmost keys has an action: on battery power, it clears RAM and disables all functionality until the charger is connected: does it short the battery??), I suppose the N-Gage solved both issues and dome buttons aren't inherently bad.

Oh! I thought the ⑤ and ⑦ keys were so that the user puts their index and middle fingers there to recreate the gesture in OP's image but now I see the key rows themselves resembling the fingers.