Care to explain what exactly is poor? Remember not all items are beneficial from a cache stand point.
I do have to agreed that Forticache is not up to standard with other common caching solutions, ( bluecoat, riverbed, WAAS, etc... ) but the configuration and deployment is very easy. We have deployed the 3000Cs and a few 1000s and so far we are on the line with the benefits over vrs the dollars spent.
FWIW; we had 3x units that exhibits out-of-box failures that gave us problems before even going live ( 1x bad ethernet port and the other 2x had a bad drive or something storage related that required a RMA )
A PC is ideal if you do happen to have intentions with buying any cache appliance. I'm not sure how you can really compare a virtual appliance with regards to performance against the hardware appliances tho. If you are not 100% happy, speak to the channel manager and/or better the product manager.
ken