Me and a mate went to the Nec and were very tempted by Autocom to be honest. We eventually didnt because of me, basically, I didnt want to the hassle of trying to locate the unit on a 999. However, when we came away, we did a bit of research, and eventually bought the Pro 6, which can be powered by a 9v battery. So, we both bought one and chucked them in bum bags.
We use them with Alan Pmr446 radios, and I can honestly say they work like a dream. Tested at 130mph and still quality is fine (Both Astro Race lids).
What I would say however is, as mentioned before, fitting of the mic and headsets in the right location is essential, especially the mic.
Oh, and if you consider buying one, you may like to look on ebay, as this is where we got ours from. It was from a supplier in Guernsey (Vat Free), and the whole kit, Pro 6, phone lead, bike power lead, headset, mic, came to just under £120, cheaper than Autocom themselves.
This is the link to the seller, drop her a mail and check availability.....
http://cgi.ebay.co.uk/AUTOCOM-HEADSE...cm dZViewItem Neil