Interesting subject this, my five came with 32/22 double & 11-36 block, once drive chain wore out I opted for a 1x10 setup! To keep it simple I choose RaceFace N/W 30T up front & kept 11-36 ratio's at the rear!, did some research regarding one up components 40T, modded cage to reposition the top jokey wheel etc! my main concern was possible premature wear due to the quite large jump to 40T or 42T & chain cross? The 30T feels nice with the added benefit of being able to clear most if not all log rolls etc! and able to climb most terrain , Warely , SH ,fair amount at Ard Rock!
I follow Ed Oxley on social media he also runs 30T 11/36, He's local to Hebden Bridge, he was once asked "why not try 40,42 out back" & he replied " kept things simple & make's you a stronger rider" Can"t argue with that lol!
Worth noting what Mr V said important factor not to over spin your legs!
Wouldn't mind trying an oval ring as may help stop bobbing when climbing for long periods
Did also look at the 11-40 block but 34 to 40 is quite a gap also, gonna wait for more reviews!