Thanks for the input Digerati, but I understand how to troubleshoot dropped connections - and the myriad things that may cause them.
What I need is a tool that will document the network activity on a customer's computer at my shop - and will show that (hopefully) there are no drops at my shop. It'd also be nice if it had a display/logfile simple enough to easily explain to a customer.
The company will put a decent amount of money into it - they've purchased rights to a lot of software that we use.
The best thing that I've found is FreeMeter - but development stopped on it in 2010. Haven't tried it on Win8 as I doubt the company will want to purchase something that old (and without decent support).
I'm also looking at NetWorx, but haven't really done anything with it yet.