2 MacBook Pro's - Which one do I sell, which do I keep?

I bought my MacBook Pro in the UK in late 2009.
My boyfriend bought his in the USA in 2011.

Now we are married and we only need one. We want to sell one , keeping one for ourselves. Not sure which is the better machine to keep though:

HUSBAND'S MacBook Pro
* Model Identifier: MacBookPro8,1
* Processor Name: Intel Core i5
* Processor Speed: 2,3 GHz
* Number of Processors: 1
* Total Number of Cores: 2
* L2 Cache (per Core): 256 KB
* L3 Cache: 3 MB
* Memory: 4 GB
* Boot ROM Version: MBP81.0047.B0E
* SMC Version (system): 1.68f96
*
WIFE'S MacBook Pro
*Model Identifier: MacBookPro5,5
* Processor Name: Intel Core 2 Duo
* Processor Speed: 2,53 GHz
* Number of Processors: 1
* Total Number of Cores: 2
* L2 Cache: 3 MB
Memory: 4 GB
* Bus Speed: 1,07 GHz
* Boot ROM Version: MBP55.00AC.B03
* SMC Version (system): 1.47f2

Advice is much appreciated! Thank you in advance.

The Intel Core i5 processor is much faster than the Intel Core 2 Duo processor; however, depending on what you use the computer for, the Intel Core 2 Duo might be fast enough.

If performance is the only criteria you care about then keep the Intel Core i5 one.

If the Intel Core 2 Duo one is fast enough for everything you do, then keep that and sell the Intel Core i5 one (since you'll get more money for it).