"OEM" is the new modded.....
Once you put lots of goodies on, it will still be worth the same as it was before. So people strip them back to standard anyway and sell the goodies they put on.
Ask P15UL T for details!
If you are using the 350 as a gateway to the 370... i.e. you want to sell it eventually to get the 370, then I would keep it standard and save your cash...
Just keep her lovely and stock. then when it comes to selling her, she will be more desirable than the stock one's you are up against in the selling stakes.
You can still spend PLENTY of cash getting them to standard and keeping them mint... AND have fun.