If it is the same connection as the T61, which I think it is, then no a SATA HDD in the Ultrabay is nowhere near SATA II speed. For me it got nowhere near saturating SATA I. On benchmarks (ATTO) of the same 7200 rpm HDD I was hitting 75ish MB/s in the main bay while only getting 15-20ish MB/s in the Ultrabay. It's no competition with a SSD. After Middleton BIOS flash I was hitting 185ish MB/s in the main bay while still the anemic 20ish MB/s in the Ultrabay.
Also AFAIK, like a T61, don't you have to flash Middleton BIOS to get SATA II speed in a R61? If so you'll only get SATA II speed on the main SATA line not on the PATA line (which is what is connected to the Ultrabay).
Only way to know for certain is to benchmark yourself. And as stated above, T430/T530 Ultrabay adapter won't physically fit the R61.
That's a bummer. I used to be convinced by my findings that HDD performance is equal in and outside of ultrabay.
Anyways, your benchmark seems a bit low. I just found a post by a guy who was getting SATA I speeds out of Ultrabay HDD in T61 (here: viewtopic.php?f=18&t=106731
Perhaps there is a firmware bug, as described here: http://forum.notebookreview.com/lenovo/ ... reads.html