Have had three: a crappy Chinese made BAM (which they stopped selling for obvious easons), and old model FX, and a Hill. The FX and Hill I still use.
The Hill may move a little more air than the FX, but not a great big amount..maybe 4%. IF it takes 100 umps to fill with the FX, might take 96 pumps to fill with the hill...nothing to get excited about, esp. as the Hill takes more effort to pump at higher pressures than the FX.
Hill is the eaisest one to take apart and rebuilt if/when needed. FX is smaller and lighter, more portable. Hil;l takes a bit more effort per pump, but it's not a problem (am an old guy, 165 pounds, pretty active shape, and have no problems pumping these guns up...heavier folks would probably find it easier as their weight helps on the down stroke).
How much effort it takes to fill a gun depends on how high the pressure and how big the gun's air volume. Pump effort gets pretty heavy past 2500psi and the larger the volume to be filled, the more pumps it takes to do it.
PCP's start to shoot slower as they shoot down and pressure gets to some certain point. How low depends on how the rifle is tuned, some will start to show significanlty slow shots while still up at 1400PSI and others will be tuned to shoot well down to 900psi. Either way, most of us stop shooting a little before that "fall off pressure" and either refill the rifle or put it away for next time.
Depending on the rifle's (or pistol's) performance , may be no good reason to fill to the listed max. PCP's also tend to shoot a little slow at first until they get down to the optimum pressure. So the gun might be rated for 3,000psi, but if it doesn't start shooting it's best until 2800psi, why put in the "extra" 200psi?
Can fill a little air tube, Like the 122CC tube on an AA S200, from 1200psi to 2700psi (which happens to be where mine is set for it's best shooting) with about 50 pumps. Can fill a Sumatra (think the volume is about 480c) from 1400 to 2900 psi in about 125 pumps. Discovery would take about 55 pumps to go from 1000psi to 2000psi.
I'll pump in sets of 50-60 pumps, then let the pump cool down before putting in another set of 50-60. Will VENT the line between sets to bleed off moisture. that's why it's 50 to 60, as it takes a feew pumps to repressurize the line until the gun's fill nipple clicks open. Makes more work for me, but the pumps are lasting a long long time between rebuilds and I've not found any moisture problems inside the rifles they fill.
I can't think of any pistols with large air volumes, so filling by hand pump shouldn't be a problem.