All the vega conversions seem to perform really well. The kyosho has more of the top drivers running it so there's probably more support for setups with that chassis.
The B4.1 will be a great car and spares availability will be good because of the popularity of the base chassis.
If spares support is a concern, we will be introducing a full range of kyosho spares to our website in the next week or so.
The choice is yours!