Is there a local version of Studio we can view things on?

Jake_N Besides making Lithium look for your locally compiled CSS in Studio (as TariqHussain wrote above) you will need to tell the SDK to serve/compile the SASS with

li serve-sass

that is because your skin usually depends on other skins (e.g. responsive peak, base, whatever) that you do not automatically download with

li export-studio-plugin
// or
li export-plugin

see here: https://community.lithium.com/t5/Developer-Documentation/bd-p/dev-doc-portal?section=responsive#l::{"p":"%2Fsection-developerguide.html","h":"%23localSkinDev"}

To speed up the time it takes to submit the plugin, I would recommend you to only export the stuff you often work on, e.g. limit the plugin points as much as you can, the more is inside the plugin each time it is submitted, the longer it takes...this can be done with the points flag, e.g.

li export-studio-plugin --points "skin,component,macro"

if you want to keep track of everything with version control I'd advise you to create a separate "develop" branch where you to the above, within the "master" branch or "full" branch you can have a complete export of studio still... but limiting your plugin points will help a bit with the speed issues...as you say, it doesn't make much of a difference if you save trough studio or submit an SDK plugin, both are painfully slow...

Guess you know the SDK docs already, but here they are anyways =): https://community.lithium.com/t5/Developer-Documentation/bd-p/dev-doc-portal?section=sdk