Hmm... I see that it's implemented differently, but aren't they accomplishing the same user task? Fundamentally, they're both solutions to the "this file is too large to email" problem. Or am I missing something?
The free version of Letscrate limits files to 50MB and your library caps out at 200MB; the $9/month plan allows larger files and caps out at 10GB. Sendoid is free for all file sizes and imposes no caps on the size of your library.
Letscrate offers no security measures. Sendoid creates an encrypted link between sharer and receiver, and has options for password-protection and one-time usage.
I couldn't try that with Crate (I don't have a pro account) but uploading a 25 MB file had taken 10 minutes before I gave up and decided it wasn't worth it.