I picked one of these up used on e-bay for a good price. It's the right size for what I want to use it for, and it is Part 15 certified. It is also RSS210 certified in Canada - RSS210 is pretty much identical to Part 15 but for one small caveat. RSS210 cannot be used for broadcasting - for that, you need to use BETS. The basic technical requirements for BETS are the same as in RSS210, but BETS allows 4 times the field strength of RSS210 in the FM broadcast band.
And here is where it gets complicated. There is no BETS certification. You can only get RSS210 certified transmitters. If Industry Canada stops around to inspect your broadcasting studio, you have to show BETS compliance only. If your transmitter is RSS210 certified, then by default it is BETS compliant, and you are also allowed to increase your field strength up to 4 times that of RSS210.
With the legal stuff out of the way, I was very impressed with the sound quality of the Whole House 2.0. I really couldn't tell the difference between it in mono mode and my Decade MS-100. I used a quality USB AC adapter (not one of those dollar store el cheapo's) to power it via its USB port and I noticed no hum (you can also use batteries or plug the USB into a computer, but I didn't attempt either). I do all my audio processing external to any transmitter I use, so I didn't even bother to use the AGC. Much has been made about this transmitter being prone to overmodulating, but I didn't find that was the case. The input control on the Whole House is fairly coarse, so I just put it on the setting where it started to distort, and then backed off the volume on the audio chain side. In doing that, I was able to get a clean, undistorted signal transmitted that was as loud as anything else on the FM band.
Now, the Whole House comes with an antenna extension kit for countries other than the U.S. that may have more liberal rules. In another review, with that kit installed, the field strength of the transmitter was 1000uv/m at 3 meters - exactly the maximum allowed in BETS. I don't have the required instruments to measure field strength, but I did notice a definite signal increase with the antenna lengthened, and it appeared to approximate the range obtained by my BETS compliant Decade transmitter.
The build quality of the Whole House is definitely not up to the standards of the Decade, or my other FM transmitter, the Landmark FM-350 (both Part 15 and RSS210 certified). It is made out of lightweight plastic, and looks and feels cheap. But then, it costs a fraction of the Decade and the Landmark. I noted that the LCD panel was not fitted on straight, but I don't know if that was a vagarity of my particular unit, or standard across the product line. I also don't know how long the transmitter would hold up under continuous 24/7 transmitting - you certainly wouldn't want to give it a bump of any kind.
It was fun to test this out, but I don't think it will replace my Decade. I wanted to put a transmitter on a window sill, but the lengthened wire antenna is very long, and it just won't fit vertically extended (my townhouse complex doesn't allow any sort of outside antennas). I think I'm going to put my Decade on the 3rd floor on top of a dresser overlooking the window and see what kind of range I can get there (it's pretty poor right now on the first floor).
All in all, the Whole House is a great transmitter for those who want to get into FM microbroadcasting on a limited budget, either in Canada or the U.S. (those in the U.S., of course, can't use the antenna extension kit legally). New ones go for about $150 on e-bay at a buy-it-now price, and the seller also usually has several on auction that go for anywhere between $100-$150.
I'm probably also going to sell the one I have in the near future.