Saw Pat recommend the 8251 in another thread. I have been using the 8261 in my Procharged 20lb boost, 7530T setup. Always keeping an eye on that ( I'd love to avoid the MSD 8, 10 ) and want to get the most out of my combo.
From the spec sheet the 8261 has 70 turns and a 2 amp / 45,000 volts output where the 8251 has 85 turns and 1.1 amp / 45,000 volts output.
By comparison the 8201 Pro Power coil has 100 turns and .8 amp / 55,00 volts output.
Maybe Pat can shed some light on where voltage is more important than amps
The reason I recommend the 8251 over the 8261 is the cost of admission. And for the testing we have done on different platforms using both coils we have found that either will give you equal results. Now if I hook the coils up on the bench and attach an Oscope I could show you a difference out of the 8261 coil but it just does not translate over to track or dyno numbers. I hope this helps!