What is your experience with amp power?

Some speakers benefit from current and damping.   Not all watts are created equal.    Most good SS amps deliver a lot of current and have corresponding high damping. Not a fan of lesser built high power SS amps that deliver lots of watts but not much current with most speakers. 

In general smaller speakers with extended bass, which tend to be the most popular and the least efficient, require high power high current SS amps to sing. Larger and more efficient speakers may be easier to drive but often lack of extended bass is the reason. So you have to know what you are dealing with in regards to speakers and how well they might perform in a particular room and make sure the amp is up to the task. That’s basically it in a nutshell. Bigger rooms are harder to conquer. Small ones not so much. It’s largely a matter of scale. Just avoid clipping or over driving a lesser speaker. The devil is always in the details.

More power doesn't now, nor will it ever, equal better sound. If that were the case, a 2A3 Sun amp would sound terrible since it puts out a whopping 3.5 wpc. This should be common sense but based on most of the tripe posted here, common sense in the audiophool world isn't very common.

Some build a system around a speaker, some around an amp. Pretty loaded question with many possibly answers... I might venture to say though that the beauty of an amp be not judged by it's power!

I'll share my experience. Along with a pair of Legacy Audio Focus speakers which are low to mid 90's efficient, I was using a Plinius SA-103 power amp that delivered 125 watts into 8 ohms and 220 watts into 4 ohms. I always felt that it lacked a bit of power and indeed there were times when listening at high volume levels during a sudden transient, it would go into protection mode. I decided to sell it and replaced it with a Plinuis SB-301MKII which offers 310 watts into 8 ohms and 470 watts into 4 ohms. The improvement was amazing. I had a much deeper dynamic range now and everything sounded more balanced across the frequency spectrum. I have never driven this amp into clipping or protection mode and I'm afraid to think what it would take.

In contrast in my second system, I am driving Legacy Audio Signature III's with a small Plinius (yes, I like Plinius and Legacy together) 9100 integrated rated at 120 watts into 8 ohms and it drives them with authority. I recently picked up a small EL34 tube amp that puts out a whopping 8 watts for another project. I hooked it up to the Signature III's and was amazed at how good it sounded......with the right music! And there is the rub! When playing a cut from say, Passenger with an acoustic guitar and vocals it has plenty of power and can play loud. In contrast switching over to a London Grammar track with lots of deep bass, you can hear the tubes go into clipping easily. As a matter of fact, it can barely play some of their tracks.

So my conclusion is, the more power the better except in some circumstances where you may be listening to acoustic music or light jazz then you can get away with less power. The key to each of the aforementioned amps is current and power rating together. I would never drive high efficiency speakers with high power however so there are always exceptions to the rule.