Options for 2nd SSD in Optical Drive bay

[ssatpathy]

I have a T410s that is ripe for a storage upgrade ( originally came with an Intel Gen II, 80 GB 1.8-in form factor). I was considering getting a 160 GB 320 series drive in the 1.8-in form factor but they are slightly more expensive than the 2.5 " form factor drives and I hear the 1.8" drives are a dying breed.
So I am onsidering getting a 320 series 160 GB , 2.5 " drive instead and adding it in the optical bay using a bay adapter and leaving the originally boot drive alone ( since the 2.5 " in form factor drive would not fit in the internal slot on the T410s since it supports only a 1.8-in drive).

I need some guidance on the following :

(i) Of the two thicknesses available in the 2.5 " form factor which one fits the Ultrabay III adapter - 7mm or 9 mm ? I am hoping it would be the 7mm but I may be wrong.
(ii) Could you kindly provide the part # for the 160 GB drive in the 320 series ( retail box preferred since that provides the 5 year manufacturer's warranty) that would be the one I need to procure ?

Thanks in advance.

-Subh

[ZaZ]

I'm just curious why you'd want to add a second SSD when you've already gone one in the main bay? Most people use the modular caddy for storage where speed isn't as important. A SSD will cost more and offer limited capacity.

I haven't tried it myself, but I would think the caddy would accept either a 7mm or 9.5mm drive, but the 7mm drives are more scarce, which means more expensive. The 9.5mm drive will work just as well.

The Intel part number for the drive is SSDSA2CW160G3K5.