I would highly recommend Sound Telecom on every level. First-class operation. Professional and responsive. Not one complaint or concern.
Does your organization have a witty catchphrase or slogan? If so, use that to your advantage. Here is one that could be tailored towards a custom software company:

I have a confession to make: I haven’t recorded a new voicemail greeting since 2014. In the past four years, I (hopefully) have become more articulate, poised, and self-assured. But hear my voicemail recording, and you’d think I was still new to the work world, a little unsure of myself — and probably not an authority. Obviously I need toupdate it. And if you haven’t changed your voicemail greeting in over a year, you’re likely in the same boat. After all, a professional voicemail recording boosts your credibility, makes you seem more competent, and encourages whoever’s listening to it to continue the relationship. A relatively unprofessional one — like mine, for instance — does the opposite: It encourages prospects, recruiters, and potential connections to run in the other direction. With that in mind, I’ve written 18 unique voicemail greetings for every situation. Pick your favorite, practice a few times, then record your new voicemail.
“Hi, thanks for calling the office of (insert your name). I’m away from my desk or out of the office. Please leave your name and number, and I’ll return your call as soon as possible. If you need immediate assistance, please hang up and reach our customer support team at (insert phone number). Thanks, and have a great day!”