Catalogue & checkout
Gambio
Variants, tiered pricing, vouchers and B2B are confirmed, which is solid conversion groundwork — but the payment story is just "PayPal & Co.", with no invoice or direct debit evidenced, and no bundles, guest checkout or rule-driven promotions in the evidence. Checkout changeability beyond the StyleEdit design tool is unevidenced, so I sit between the anchors.
Shopware
The variant machinery is real — parent-child inheritance, a configurator object, unlimited property groups for filtering — and the payment architecture with synchronous and asynchronous handlers and the redirect URL returned in the API response means checkout can be reshaped without a rebuild. But we found no public information on invoice or direct debit as payment methods, on promotions or voucher rules, on guest checkout or bundles, and customer-specific prices appear only in the top Beyond tier.