The only way to tell if you get better sound with a separate power amp is to listen and decide for yourself. Some hear an improvement, some don't. Your room is small but a lot depends on how sensitive your speakers are, how much sound absorption your room has, and how loud you like to listen to movies/music. As a previous poster said, it takes a huge increase in power to noticeably increase the average SPL (sound pressure level). Most listening requires only a few watts if the sound level is steady, but that changes drastically when dynamics enter the picture. If you want to hear explosions or music in anything approaching realistic levels your system may require several hundred watts of power at 4 ohms to reach that without damaging your speakers because of compression and/or clipping during dynamic peaks. That is one of the main benefits of a separate power amp because few receivers can produce that kind of clean power, and probably none of the usual mass-market receivers will do so. Receiver features change constantly in an attempt to get owners to constantly upgrade (hopefully before the receiver burns itself out). But a good amplifier is a good long-term investment; most will last for years without any issues, and many have 5 year warranties or longer (Bryston amps get 20 years; Paraound 10 years; Classe and Sanders amps get lifetime warranties). I moved from a receiver to a separate amp primarily to assure the good health of my speakers, which were a major investment. And over the years I have found subtle but distinct differences in what each amp produced sound-quality wise. But that is just me, and you may not hear that at all. IMO a separate power amp is a sound and worthwhile upgrade for most receivers which can be used as a pre/pro, and there are some great used amp bargains to be had at Audiogon and Videogon. That is where I bought my current amp as a demo unit with full warranty. Anyway, as I said, the only answer to this question is a personal one and only you can make the call.