Not sure what servo your going to run in your crawler but most of todays 'comp worthy' servos, draw well over what most internal becs can handle (the HH being the only except but it's still only 6v). If your running 7995, 7950, S9157, 7980/7990, 7954SH, 8711 your going to want a CC bec minimum for power wise. Remember crawlers work servo's A LOT harder than other applications. Plus most of those need around 7.5v to get the most out of them

Also I am pretty sure the HH is a completely different board to the sidewinder original and SV2, the only similarity is the sidewinder case. Which is shared with a number of ESCs now.
Kieren