this is a 2 part answer.
Feet Per Second (fps) both guns are adjustable and should be reduced to fire at around 280fps for best effect and safety.
Rate of Fire (Rof/Bps) both guns are capable of 8+ Bps without any mods, however an electronic/responce trigger on the A5 will cap at around 18-22 bps, and the SP1 at 15-18 Bps.......most fields wont let you shoot faster than 13-15bps, so these numbers are perfect for most needs.
The SP1 is the better marker. For nearly the same price you get a better valve (spool valve) a regulator, full auto electronics, a better feed neck, and an in general better marker. The only advantage to the A5 is the cyclone feed, which shoots faster than a regular hopper, by using excess CO2. It also does not feed as fast as the sp1 can shoot an has a tendency to jam in the winter without squishy paddles.
The sp1, because it has a regulator.
if it is a 223 cal, then yes
Depends on markings on upper.
approximation: 300 feet.
Recommend you have it examined by a gunsmith.
Depends on when it was made. Go to Browning.com and ask.
Try online auctions.
Use a gun that allows you to shoot fast and use gun booster.
No, SP1 is included in the updates of SP2.
As fast or a little faster than a basic one.a good buy.
2500+ fps and it could shoot as long as you want in eyes view.