What are some alternatives?
Short Domain Search - Find short, available single-word domain names
Amazon Route 53 - Amazon Route 53 is a highly available and scalable DNS web service.
Weird One Character Domain Superstore - Weird and available one character domain names
Google Cloud DNS - Reliable, resilient, low-latency DNS serving from Google’s worldwide network of Anycast DNS servers.
DomainWatch - Domain Monitoring Made Easy
Domainz.io - Premium domains, for not so premium prices