u/FGK_

For my bikepacking tour (starting on August 1 in Berlin, through Denmark, southern Sweden, and the Lofoten Islands to the North Cape; from there through Lapland, the Finnish west coast, the Baltic states, and Poland back to Berlin—arriving on October 16), I’m not sure which sleeping bag to bring.
The options are:

Sea to Summit Spark -1°C and
Sea to Summit Spark -9°C.

According to weather data, temperatures on the way back could drop as low as -3°C.

I have the Therm-a-Rest NeoAir XTherm NXT MAX Large sleeping pad (R-value 7.3), a silk inner sleeping bag, long-sleeved merino underwear, and the Durston X-Dome 1+ Solid. I usually sleep a bit on the cooler side.

Which of these two sleeping bags, or which other lightweight and compact sleeping bag, would you recommend for this trip and the season?

For a 10-week tour through Europe, I need some extra storage space. Would you recommend rack bags or fork bags, especially in terms of riding comfort?

Or do you have any other ideas?
My current setup consists of Cyclite bags (saddle bag, Top Tube Bag Large, Frame Bag XT, Handlebar Roll Bag, Handlebar Aero Bag, food pouches). Switching entirely to different products isn't really an option.

With rack bags, I could probably do without the saddle bag thanks to the extra volume and continue using the taillight from my ECLIPS dynamo system. On the other hand, I wouldn’t have any splash protection on wet roads…
With fork bags, I’d have less extra storage space and would still need the saddle bag, but I wouldn’t need a rack.

Whether on the rack or the fork, I would probably go with Ortlieb Gravel Packs or Fork Packs.