I've got two years of Muay Thai traning under my belt. I'd love to learn the other two styles and become a beast like Tony Jaa. I believe it's pretty difficult to find someone to train in the other styles even in Thailand.
How long have you two been training?
Yes, Muay Boran is the REALLY powerful and bone-breaking stuff. I was fortunate to learn a little muay boran from Ajarn Chai Sirisute who teaches in the US and started the Thai Boxing Association. We have both been training Muay Thai for about 10 years now, but also mix up jeet kune do, tae kwon do, and capoeira in the mix. At this point, I can do "pure forms" for each, but I mix them up so my movements are not predictable.
https://en.wikipedia.org/wiki/Chai_Sirisute
that is the link to Ajarn Chai's Wiki page