Yeah. I've written the guidebook book on what NOT to do with Leo's old BOSC Amplifiers. Personally, I prefer the Ultra Amplifier. More WPC and Tons of protection.
Yes, leave the Amp on all the time is fine if your Preamp or Line out from an AVR/ AV Preamp is also left on all the time. Those loud 'Pops" when you hot swap stuff on those little Amps can and in my case, will fry a driver (or two). Not to mention cause the Amplifier to go up in smoke.
While I love the sound those little 150W Wonders make. They couldn't drive my Series 1 901's. But the Ultra does !