Yes, I've been using it. It (the JY-MCU based board) is also what Xopti was using in his before he stopped making them. If you read the reviews, they talk about the description being wrong and that it indeed has the 5V/3.3V bridge built in.
That is a BT module sitting on top of another board The bluetooth chip itself uses 3.3V. The board that the chip is set on takes 5V input and steps it down to 3.3V.
In your link, the RN-42 chip is 3.3V as well, but the board is 5V input. Here's the RN-42 by itself: https://www.sparkfun.com/products/retired/10253
If in doubt, an LM317 VR could be used with a couple resistors to get the exact 3.3V, but that still would not break the bank since they're almost half the price; similar-priced when you add in the cost of the necessary resistors.
His excuses are not adding up...literally.