I have not had a Marshall amp since the 80�s so I�m only speaking for Fenders. In my opinion OD-1 sounds way better with Fenders than SD-1. In my (humble) opinion SD-1 is not on par with OD-1 in any situation. I have a MIJ SD-1 so I�m not comparing a new SD-1 with the OD-1. Take notice that this is my opinion!
I have been lazy over the years in trying out different amps, and my knowledge of tubeamps is fairly limited. I have however seriously considered sometime buying a good tubeamp that works well with Boss pedals.
In my opinion Marshall has too much gain for working really well with pedals, you need a tube amp with large headroom running at the point of breakup. Of course pedals will work fine with Marshalls but if you�re looking for the perfect amp for pedals I would recommend traditional Fenders or clones of them. Delays, reverbs and many other pedals don�t like too much overdrive after them. Again this is my opinion�
This topic may turn into a debate Fender vs Marshall�. In the late 80�s I had a 60�s plexi Marhall 50W top and cabinet with Greenbacks (the ones that are supposed to be really good) for some years but I didn�t like it too much. So before and after that I have nearly strictly used Fenders. You got to keep that in mind when reading my opinions above.
It depends a bit what sort of sound you're after. If you're looking for the Zakk Wylde type of distortion I guess a JCM-800 together with the SD-1 will be spot on. If you're not looking for a real high gain sound I agree with Goran that the Marshall has too much gain.
High gain amps like Mesa, Bogner, Engl etc will be even harder to drive over the top with a distortion pedal in front. There is an awful lot of amp makers out there so don't narrow it down to Marshall before you've looked at the whole market.
You don't mention anything about what your budget is or how much effect you need. A preference about what type of sound you're after would also help.
Im not in the process of buying one at the moment, but just thought it would be interesting to get some opinions on different gear.
I play a variety of rock with a wide range of distortion, and I suppose both Fender and Marshall, and others might satisfy my needs depending on what mood Im in for the day...
Never thought that my OD-1 would sound as good as it does through my solid state Hughes & Kettner amp...but with some tweaking of the amp eq and my GE-7 I get a really good sound from it.