Better performance: USB3 in ExpressCard/34 or 2nd HDD in place of SuperDrive?

[nfable]

Been Googlin' for a bit now as I need a more portable solution than my eSata OWC Mecury Elite for additional storage.

This brought me to LaCie's USB3 solution:
LaCie Rikiki Superspeed 750GB in conjunction with LaCie's USB 3 ExpressCard/34 adapter

-OR-

Going the 'Data Doubler' route of removing the SuperDrive and using:
This drive tray caddy and this Hitachi drive

Yes, I know the LaCie EC/34 can only be used with LaCie products - don't care, but I have read it may need to gobble up a USB port to power a drive .

I like the all-in-one (and slightly cheaper) aspect of the 'Data Doubler' option; but will the speeds going I/O be better (or as good) as what the LaCie would offer, or in comparison to my current eSata hook up?

Much thanks for any illumination,
nf

 

[Freyqq]

2nd hard drive in superdrive by far.

First, there arent any USB3 drivers that i'm aware of for osx. Second, USB has higher CPU utilization than sata. Third, current gen MBP have 6 Gbps SATA III, while expresscard/34 maxes out at 2.5 gbps.

 

[Prodo123]

2nd hard drive in superdrive by far.

First, there arent any USB3 drivers that i'm aware of for osx. Second, USB has higher CPU utilization than sata. Third, current gen MBP have 6 Gbps SATA III, while expresscard/34 maxes out at 2.5 gbps.

Not all the MBPs have SATA-III in the optical bay slot.
Either way, internal > external for now.

 

[nfable]

My MBP is a MB604LL/a, so I think I'm at Sata II.

LaCie has custom drives for their USB3, but the rub is it ONLY works with their drives. (Can't be that picky can I?)

I think the internal is the way to go in light of saving bulk and some bucks.

I appreciate the input, any more is welcome...

nf