PDX You can pick up a decent HO 'power pack' cheaply and run the MTH locomotives. I recently acquired a few of them and really enjoy the quality and detail of these newer locomotives in HO. I've also joined a local club about 45 minutes away that has a very nice layout all set up with the modern Wi-Fi control that allows me to run all of my HO equipment from my iphone at no cost by not having to purchase any additional electronics.
Give it a try - You'll be pleasantly surprised...
PS I have a MTH set of UP Alco PA's and have an extra B unit that I haven't used. It is powered, has PS3 with full sound and smoke and can be run independently that I would sell for $125 mailed to you if you'd like to try one with little investment. It's NIB. Try buying a PS3 locomotive new for less than $250 elsewhere! :-)