So far, so good. I have been using the software for quite a while now (OS X version) and it does the job to the extent one can tell! With any backup software you need to try and test your backups and, of course, have faith in the entire process).
Of course there are things that the developer could improve on - there is no megacorp behind the company here - yet the developer should be credited for the work done so far.
From my own experience, a lot of the "problems" are caused by the backup destinations being used. OneDrive seems to be like a snail overdosed on sleeping tablets (no matter what location I try and emerge from) and the newly added Amazon Cloud Drive has been rather problematic (the developer is having to go to the ludicrous situation of trying to fix Amazon’s own problems and shortcomings in software as a temporary measure). Google Cloud seems to work and my own S3-based instance has been trouble-free.
My own extensive troubleshooting experiences with the developer have been positive. Of course, you want faster responses as obviously your own problem is the biggest thing in the world (self-referential irony) but practically you know that there are many customers to support, future developments to code, bugs to fix and maybe even find the occasional hour for “me time”.
If the user is able to give additional information above “it don’t work” this can help or speed up the process.
It would be nice to get a roadmap of planned developments, a feature request list and other fine things, yet Rome wasn’t built in a day. It does feel that uploads are slow, even when backing up on the LAN, compared to non-encrypted transmissions. It can be a perceptional issue or areas of speculation that may be improved in the future. It would be highly desirable to have a bandwidth usage meter so you can see it is currently backing up at X speed, then you can have an idea that backups to OneDrive usually are around X Mbit/s, Amazon X Mbit/s etc. For those with more powerful computers and several backup locations, multiple (simultaneous) backups would be good, especially when uploads don’t tax your uplink speed and you have a lot of data to initially seed.
If you don’t feel the developer responds quickly, maybe he has not got the mail (there was a problem in the past with the “request support” link in the software. Email has worked and the developer also answers Twitter.
TL:DR: Still a best of breed and getting better, despite the provocation some backup sources can create when they break things at their end.