rocket mass heater with flue pipes v stratification bell chamber

Hi All,
Greetings from your cousins the other side of  "the Pond"
I am caught in 2 minds weather to build my RMH with the pipes running thru the bench, or to go with the Hollow bench  stratification method. Has anyone built the stratification model?   There are plenty of posts about the pipe method.   I would like to go with the Stratification method, its seems easier and cheaper to construct, but i am worried about there being sufficient draw.   I guess if the hollow bench was not great, its easier to deconstruct it and build the pipe method, than the other way around.  Matt at Taylor stoves has been fantastic with his advice, i just wondered if any permie had built one.  I have purchased a Gamera" stove from Bulgaria, like the Uncle mud guys use, so its only the bench i am concerned about.  Any thoughts?

Apologies, that should be Matt at Walker stoves, typed in haste...head full of gas and flue pipe!, apologies to Matty as well

Welcome to Permies from a fellow Brit!
Both systems have advantages and disadvantages as I understand it. I think if you have your own source of clay, then the cob bench can be a very cheap method, but lacking that (like I am) a bench bell is simpler. The flue gas draw is mainly provided by the internal 'chimney' of the riser; this provides the main impetus to the gases. It's been found that a good chimney is really essential as well to allow for adverse climatic conditions - in milder climates like ours, or windy ones like mine. A bypass to the bell can ensure a good draw until the stove gets warmed up.
Caveat: I've not built a system yet myself, but have plans.....mine is going to be a bench bell I think. If I was starting again in this house I might have a walker tiny stove in my kitchen instead of the wood fired range we have now.

Hi Nancy, were in Cornwall.  Have you looked at the Gamera stoves from Bulgaria, we have purchesed one, just got to build a bench, but cant make our minds up which method to go for, only want to do it once!!

No I haven't looked at the Gamera stoves. I think they've had pretty good reviews, (I thought they were stand alone?) but I think we'll maybe go for a j tube firebox out of firebrick ourselves. It won't happen for a few years yet in my case here's my thread if you're interested.
Hopefully someone with more experience will chip in for you.