This is a comparison between Shop Local's Syncing service and Shopify's Collective service.
What Product Does Each Service Sync?
Shop Local's Syncing service shows a brand's entire product offering by default. Collective does not. For example, if Vagabond House offers 1,000 products, Shop Local's Syncing service will show those 1,000 products by default on the merchant's Shop Local Store. In contrast, Shopify's Collective service will most likely show a small fraction of that on the merchant's Shopify store.
The Process To Initiate a Sync
Shop Local's Syncing service is a one click solution with no little or no planning needed by the brand and retailer. For example, a brand can simply Sync with a merchant without considering what will be Synced.
When using Collective, the brand has to manually select which products it wishes to shares with the merchant. It must do this for each merchant. If there are 30 merchants, it must doe this 30 times.
Promotion
Shop Local's Syncing service gives each brand a public page that explains the service's benefits to merchants.
Example: https://juliska.myshoplocal.com/about-shop-local.cfm
Collective does not offer such a page to clients.
Shop Local's Syncing Service Is Integrated with a Wedding Registry Service
Shop Local's Store comes with a gift and wedding registry service.
Since Shopify does not make gift or wedding registry software, Collective lacks a wedding registry service. A merchant would need to use both Collective and a third-party registry app to offer the products via a gift registry service.
Even if the merchant has a Shopify registry app, since Collective often only helps a merchant show a fraction of what the brand offers the gift registry service in turn only shows a fraction of what the brand offers to the registrant. This results in a smaller sales funnel and fewer registry purchases.
Newsletters & Updates
Shop Local merchants that Sync data are shown alerts on their Dashboard when product prices change or new products are released. There are dedicates pages in their account that show new items and price changes. For example, if a merchant wanted to see what price changes were made last week by the Syncing service, it could.
The Syncing service also emails merchants a weekly email with product changes, new introductions, and archived products.
Collective does not offer alerts or updates regarding products. When a change it made the merchant is not alerted. There is no email alert system.
Interoperability
Shop Local's Syncing is available to any brand and merchant regardless of what other software they may use.
Collective only works between two parties that use Shopify. If one doesn't use Shopify, it won't work.
Conclusion
Even if a merchant uses Collective, it likely won't see a notable change in sales because without a gift registry service the synced store won’t sell more. Indie stores need the online gift service and the synced products to sell more---they often can't improve sales with just one of these elements.
Collective may be a good way to update the merchant's in-store Shopify POS prices. It may not move the online sales needle but it could help with the POS prices.
Resources:
https://www.shoplocal.org/syncing.cfm
https://www.shopify.com/collective