Bingo Papanate, Earcatcher, that's where its at! And thanks all the rest for your suggestions!
I didn't have the ROI acronym with me when I posted. So much to sink in, and I'm still trying to get a grip on things while running sessions... only get 1h to get my head sorted each day
Like I said, valves has a definite finite lifespan, PC's we also know are worth for 2-5 years.
Obviously I'd expect a BAE 1073 to last a lifetime, if well maintained, and I also *could* expect that from a GAP73, but there is a world of difference between the two, in terms of build quality/robustness.
So basically you guys are saying to average out a *logical* frame of time, say 10 years, and to stick to it?