Certainly,Emma! Considering your existing setup, all the alternatives you mentioned are compatible replacements for the Notifier FSA-8000. Each one has its unique features, so the choice depends on your specific requirements. If you need a high-capacity solution, VLF-500-00 is a robust choice. For a more compact option with reliable performance, VLF-250-00 would be suitable. VLI-880 offers advanced functionalities, while VLI-885 provides a balanced mix of features and affordability. Feel free to ask if you need more details on any specific model!