Sorry for the delayed reply, didn't notice your posts. Regarding the quality of service:
Pros:
1. I haven't faced any down time yet. Both web based, and api based submits work well.
2. The maximum time taken to reach a recipient is just less than an hour. Average time is 5-8 mins.
3. The web control panel, though confusing is pretty neat. Has all the options you need, and even lets you check status of your messages.
4. Comprehensive logging system which may be useful for some
5. XML API for bulk submission - add multiple numbers to the same message, and a single submit. This is really what I wanted as the place I'm deploying my application won't be permanently connected to the internet. So instead of making 1500 individual submits, just one xml bulk submit will do.
6. Incoming messages supported - users can type "hi <username> <message>" and send it to 5676775 and you will receive it directly in your web cp free of cost.
Cons:
1. Plan validity period is too short (at least for my requirement)
2. No api to access incoming messages.
In all, I'd give it a 8.5/10. Really satisfied with the service so far
