Agree with all of the comments offered!
We bought our pre-owned 2010 S in March of this year after having done a whole lot of looking around at the various Sprinter-based RVs and we could not be happier with our choice.
Since we are only two traveling, outside storage our primary concern.
The large storage bay in the rear corner of the S is what sold us - we can fit large items - grill, folding table extra propane tank for grill, folding chairs etc and have room left for other items if needed.
The Winnie's are great units - not as much storage for bulkier items and the extra cost is what made the Solera our choice.
No matter what your final decision is, don't delay getting into an RV - we enjoy it so much and looking forward to retirement when we will have even more time to see the USA!