| Customer Support | How quickly and clearly the supplier answers technical and order-related questions. | Written response-time expectations, a named support contact or team, and clear guidance on installation and product selection. | Vague answers, unanswered questions about fit or installation, or no clear process for handling problems. | 15% |
| Warranty Clarity | Warranty duration, covered defects, exclusions, claim steps, and who pays return or replacement costs. | A written warranty document that explains coverage and claim requirements before purchase. | Warranty promises given only verbally, unclear exclusions, or no documented claims process. | 15% |
| Samples and Evaluation | Whether samples can be assessed for dimensions, finish, fit, and installation compatibility before a larger order. | A sample policy with stated costs, availability, dispatch estimates, and the option to review relevant product documentation. | Sample terms are unclear, or the sample differs from the quoted production specification without explanation. | 15% |
| Long-Term Reliability | Consistency of materials and finishes, quality-control practices, and availability of replacement parts. | Documented inspection procedures, traceable product specifications, and a practical process for repeat orders or replacement components. | No explanation of quality checks, frequent specification changes, or no information about replacement-part availability. | 20% |
| Technical Fit and Safety | Compatibility with the shelf glass, bracket design, installation method, and supporting wall or cabinet structure. | Clear dimensional drawings and installation instructions. Any load rating is stated with its test conditions and installation requirements. | A load figure is offered without test conditions, or compatibility is assumed without checking glass thickness and fixing substrate. | 15% |
| Quality Documentation | Availability and relevance of material information, inspection records, and applicable test reports. | Documents identify the product or material they apply to and can be matched to the quoted specification. | Generic or outdated documents that cannot be linked to the specific bracket or finish being considered. | 10% |
| Lead Time and Order Communication | Quoted production and shipping timelines, order updates, and communication about delays or specification changes. | A written quotation with lead-time assumptions, order milestones, and a clear process for communicating changes. | Unconfirmed delivery dates, unexplained changes to the quotation, or no timely notice of delays. | 10% |
| Overall Review | Score each dimension using the same evidence standard, then compare total weighted scores. Confirm technical suitability and installation requirements before ordering. | 100% |