I think this might come down to whether you mean performing, or checking out a pedal. From the "checking out pedal" side, SS is killer. I love to play pedals through my H&K Edition Blue 60. It simply projects what the pedal is actually doing. I love it.
I say it is depends on the amp and pedal. There are pedals that are meant to sound like the amp while others are meant to enhance the amp so the way it interacts with a tube amp may not work with a SS amp so you better test both together. I like Roland Cube 40/80 clean channel and it takes well pedals that are meant to sound like an amp, it does the job, I liked the sound of the Boss Power Stack in drive and crunch, I also liked the Boss Metal Core wit the cube. I watched a video by InTheBlues and he was asked about how good was the Mustang to get pedals infront like a tubescreamer, his reply was it was ok but the built in digital implementation of the TS in the virtual signal chain of the Mustang sounds better, actually he demos that amp a lot and he gets good tones in his live band videos too.
Being that said, there is something I could never get from SS that I am getting from rube preamp now, mostly in the clean and crunch channels. I think SS can do a good job on the high gain side but it is a matter of personal preference and I would not use a tubescreamer infront of a high gain amp anyay.
There's literally not a single pedal that Andy demos that I wouldn't buy (then sound mediocre to terrible using).I've kind of played with the idea of doing pedal demos on a youtube channel when I get back to Canada in a few months, with one of the key elements being a section where I play the pedal into a clean, neutral solid state amp for that very reason. I LOVE Proguitarshop and Pete Thorn and all those guys, but what you hear is 'This is the pedal through an optimised tube amp at a high volume with a collection of amazing guitars, and compressed and mastered in a studio'. It sounds great, but most of the time you don't get a good feel of exactly how the pedal affects tone. Could also help out the people with little solid state amps for practice, or beginners looking for pedals to put through their first amps.
I would not use a tubescreamer infront of a high gain amp anyay.
.Then you are missing out on one of the great high gain sounds you can get. You crank the output and either zero the gain or maybe on 1 or 1.5... then drop the gain on the amp 2 or 3 notches and let it burn. It tightens up the bottom for great chugs gives a nice edge. The mid hump of a TS pushes the input tube where it need to get crunchy.
Its definitely not the same sound as a just a straight high gain amp.