Hi,
I know I am a little late but for future reference...
I think you should definitely get the carry cot! All babies should lie flat to support their spine. Otherwise, you create pressure points and compress the spine which will have a negative impact on their physical development.
This is also the reason, why babies should not spend more than max. 3 hours in a car seat!
Please Mums and Mums to be, try to lie your babies flat as much as you can until they can hold themselves up. Putting them on their tummy is great exercise for their muscles.
The same applies to sitting them up. Don't do it until they are around 6 months and their own muscles are actually strong enough to support the spine.
Frankly, if you spend so much money on a great looking pram, make sure your little one is comforted and protected and spend the extra money on a carry cot.
Btw. we have a Stokke Xplory (incl. carry cot) and I love it and cannot recommend it enough (except if you like to go for extended walks in uneven terrain - the suspension is not good enough to support your babies spine - you will need something with bigger and maybe even air filled wheels.)
Our boys both outgrew the carry cot when they were around 5/6 months.
Good luck with your baby.