I don't know much about speech to text software, but I can't imagine that the best of it would enable me to input any faster than I can type. Besides, I don't have CPU cycles to spare anyway.
Lately, I've been using a wireless keyboard and mouse (which I may have mentioned below but didn't check just now) and am fairly happy with them: a Logitech S 530 Mac (model #Y-RAK73) keyboard with the mouse it came with... not sure of the mouse model number... it's white and silver and has a zillion buttons on it... of course, I only use the regular 'single mouse' button (call me a traditionalist).
My complaints are few... once maybe every 30-40 wakes (from **82**) the keyboard seems a bit logey... missing a character now and then. I just reboot the machine, which seems to get everything back up to speed again. The keyboard/mouse are RF-based wireless... not bluetooth (I have a bluetooth thingy, but never use it).
I'd recommend this keyboard... it hasn't got a lot of travel in the keyswitches, but decent tactile feedback, plenty of bells-and-whistles keys (none of which I ever use of course), etc... and basically I can exceed 100 wpm with it with very few typos. It wasn't even expensive... I seem to recall maybe $45. or so new via eBay. Personally, the wireless bit isn't important to me, so if you don't mind wired connections, I'd just ask if Logitech uses the same mechanisms in a wired set.
Good luck.