I've seen way too many Losi's go up in smoke to ever consider buying one, even for a bash car!
That said, i've seen alot of the stock spec nosram/LRP speedos go pop too since they added the boost timing in.
I run the tekin speedo and only have praise for it. Great support from all the Tekin guys, especially Randy Pike and i've heard nothing bad from anyone else either. Seems to the fastest, most reliable speedo right now. All at a fair price!
thats my opinion anyway