New Hardtail - Help!

Hi

First post and any help would be really appreciated. Looking to buy a new Cube hardtail and have narrowed down to the Reaction GTC SL (carbon) or the Reaction HPA SL (aluminium). Specs (detailed below) are almost identical, the carbon is just over 0.5 kg lighter but £100 more expensive. I'll mostly be riding forestry trails/fire roads.

Based on the fact I'm hoping to do a bit of touring (Scottish Islands) next year, I'm wondering if the aluminium would be more practical regarding loading some equipment (stuff sacks) onto the frame.

Finally, I'm pretty remote here and might find it hard to demo a bike so any help on the old 29er v 27.5 for someone like me (6 feet, 210 pounds) on the type of stuff I ride would be great.

Thanks in advance for your time

Reaction GTC SL
GTC Twin Mold Monocoque Technology, ARG2, Tapered Headtube, PressFit BB, X12, Integrated Cable Routing
color carbon´n´flashyellow
size 27.5: 16", 18" // 29er: 15", 17", 19", 21", 23"
fork Fox 32 Float FIT4, 15QR, Tapered, Remote Lockout, 100mm
headset FSA Orbit I-t, Integrated, Top 1 1/8", Bottom 1 1/2"
stem CUBE Performance Stem Pro, 31.8mm
handlebar CUBE Flat Race Bar Pro, 720mm
grips CUBE Race Grip, 1-Clamp
rear derailleur Shimano XT, RD-M8000-DGS, ShadowPlus, 11-Speed, Direct Mount
front derailleur Shimano XT, FD-M8020-D, Direct Mount, Side Swing
shifters Shimano XT SL-M8000-I, Direct Attach
brake system Shimano XT BR-M8000, Hydr. Disc Brake (180/160)
crankset Shimano XT, FC-M8000, 36x26T, 175mm
cassette Shimano XT CS-M8000, 11-40
chain Shimano CN-HG600-11
wheelset Fulcrum Red 66, 28/28 Spokes, 15QR/X12
front tire Schwalbe Rocket Ron, Kevlar, 2.25, LiteSkin
rear tire Schwalbe Racing Ralph, Kevlar, 2.25, LiteSkin
saddle Selle Italia SC1
seat post CUBE Prolight, 27.2mm
seatclamp CUBE Varioclose, 31.8mm
weight 10.65 kg

Reaction HPA SL
frame HPA Superlite, Advanced Hydroforming, Triple Butted, ARG, Tapered Headtube, Internal Cable Routing, PressFit BB
color black`n`flashred
size 27.5: 16", 18" // 29er: 17", 19", 21", 23"
fork Fox 32 Float FIT4, 15QR, Tapered, 100mm
headset FSA Orbit Z-t, Top Zero-Stack 1 1/8" (OD44mm), Bottom Integrated 1 1/2"
stem CUBE Performance Stem Pro, 31.8mm
handlebar CUBE Flat Race Bar Pro, 720mm
grips CUBE Race Grip, 1-Clamp
rear derailleur Shimano XT, RD-M8000-DGS, ShadowPlus, 11-Speed, Direct Mount
front derailleur Shimano XT, FD-M8020-D, Direct Mount, Side Swing
shifters Shimano XT SL-M8000-I, Direct Attach
brake system Shimano XT BR-M8000, Hydr. Disc Brake (180/160)
crankset Shimano XT, FC-M8000, 36x26T, 175mm
cassette Shimano XT CS-M8000, 11-40
chain Shimano CN-HG600-11
wheelset Fulcrum Red 66, 28/28 Spokes, 15QR/X12
front tire Schwalbe Rocket Ron, Kevlar, 2.25, LiteSkin
rear tire Schwalbe Racing Ralph Kevlar, 2.25, LiteSkin
saddle Selle Italia SC1
seat post CUBE Prolight, 27.2mm
seatclamp CUBE Varioclose, 31.8mm
weight 11.3 kg