First Build, Help/Advice appreciated

I’m planning on building my first electric skateboard, after many hours of research Ive arrived at a parts list which I think will work. Any advice on cheaper/better parts would be greatly appreciated (I live in the UK):

Deck: Loaded Vanguard Flex 1 (Going for a ‘boosted board on steroids’ look) http://www.longboardsuk.com/loaded-vanguard-deck-only.html Trucks: Caliber https://street-wing.com/product/caliber-ii-fifty-degree-truck/ Wheels: 90mm Clones from eBay VESC: Turnigy 50A (Despite being suspiciously cheap I haven’t managed to find anyone who has a broken one) https://hobbyking.com/en_us/turnigy-sk8-esc-for-electric-skateboard-conversion.html Motors: 2x eSkating 6355 190kv 3510w (I like these motors because they are sealed though they are a bit pricey, some guidance on weather you think sealed is necessary would be appreciated, keeping in mind I live in the UK so it gets wet!!!) https://eskating.eu/product-category/motor/ Motor Mounts: another eBay special (despite being shipped from the US at £55 shipped for the pair they are significantly cheaper than anything else I’ve found) Drive: eBay chain drive for max torque transfer https://www.ebay.co.uk/itm/Electric-Longboard-Skateboard-Part-Sprocket-Chain-Wheel-Scooter-DIY-Motor-Kit/263123898609?epid=2249888446&hash=item3d436810f1:g:1YMAAOSwjkVZhB6- Battery: 12s3p Samsung 30Q, but have played with the idea of 2x5s or 3x4s LiPo’s in series?? Anti-spark: eSkating Anti-spark (though I’ve seen some horror stories of peoples fuses blowing at full speed!) https://eskating.eu/product/anti-spark-power-switch/ BMS: only major component I’m undecided on, originally looking for one which could handle the charge and discharge but this has proved very difficult. Only possible one Ive found is this (http://alienpowersystem.com/wp-content/uploads/2017/09/12S-D223V1-Li-ion-datasheet.pdf) which can handle continuous discharge of 80A, would like 120A.

I know most people just use the BMS for charging as they say but limiting the current on the VESC you remove the need to have discharge protection but how safe is this? Also I’m insure how to calculate the max amperage i can draw from a 12s3p Samsung 30Q battery pack. The Samsung 30Q have 15A continuous rating which from my foggy memory of physics would give me a 45A max draw, but this seems wrong going by other builds I’ve seen?