Hi Scott and welcome to the forum.
Sorry to hear you've had issues with your Onkyo amp. I've had several of those both the Onkyo and Integra versions and have not had any issues.
Niles makes great products and those amps from what I have read are very solid. Have you looked at used ones on Audiogon or ebay?
The other company that makes an inexpensive sensing amp would be AudioSource. These can be had at great prices and their AMP-200 & AMP-300 should meet your wattage spec. I'm not sure about this retailer but this is a great price: LInk