This is not a shot at our competitors, just words of warning-
Some of the browser-based SSL VPNs have had serious vulnerabilities in their web interfaces, make sure you keep them fully up to date and pay attention to oddities in the logs. There was a good presentation on the topic at BlackHat '08, and I followed up with the speaker later. The problems are not common, but any compromise of a VPN endpoint is a very bad thing. The vendors have been responsive, so keeping your systems up to date should keep you safe.
Also, I know that PPTP is built in to Windows and is often easy to implement, but it is fundamentally broken as far as security. Astaro supports it because the market requires it, but personally I am very uncomfortable with PPTP.
