As part of the process of ordering the dedicated machine I had to decide on a hypervisor. Again my Microsoft background made my first thoughts tend towards Hyper-V. I knew for certain I wanted the host OS installed as part of the build done by Redstation; the remote management interfaces would allow me to install my own host OS, but this is usually achieved by mounting an ISO from your local machine, although technically possible, mounting an ISO from a consumer-grade internet connection is likely to try any ones patience, particularly if that ISO is multiple GB in size.
Interestingly, Redstation offered an install of VMWare ESXi / vSphere 5.0 Hypervisor for free. Now this would have the fairly significant benefit of allowing me to use VMware's solution exchange to download pre-built virtual appliances for functions like firewalling, load-balancing, or creating a VPN entry point to the lab. Of course, I could probably achieve a similar configuration with ISA/TMG and NLB, but from my experience, products designed with these specific purposes in mind provide a better administration experience as well as better functionality than the Microsoft combination of ISA/TMG and NLB in these circumstances. Going this route also allows me to gain some experience more along the lines of what a typical Network Administrator usually deals with, which is always a useful thing.
So in the end I decided to go the ESXi / vSphere 5.0 route. I can always rebuild that section of the network and go the Microsoft route at a later point, if I was to do that, it would probably end up with an experience more akin to what goes on in the wild (I'd imagine it's more common to see TMG deployed in front of an existing network than deployed and then a new network built up behind it).