I updated my mid-2010 15" anti-glare hi-res MBP with 4GB of RAM, to 8GB and an SSD, and the SSD has made a huge difference in performance.
I updated the RAM a couple of years after I bought the MBP. The memory I used is Kingston KTA-MB1066K2/8G. As a matter of interest, the RAM chips on the Kingston modules are from the same Hynix series as the original OEM Apple chips, only greater density. The RAM update itself didn't make any noticeable increase in performance.
The SSD is a 240GB Crucial M500, that I had bought for a PC, but never used. I did the upgrade in August 2014. The original 500GB Apple Hitachi drive was only linking at SATA I speeds, so, not counting the SSD performance, just the increase from SATA I to SATA II was a big improvement.
Along with the SSD mod, I updated OS X from 10.6.8 to 10.9.4, then to 10.9.5. With Mavericks, the MBP now takes less than 10 seconds to boot, not counting password entry time. As an example, Numbers now starts before the first dock icon bounce completes. Also, I have trim enabled with Trim Enabler.
My Blackmagic test speeds are 265MB/s read and 245MB/s write, not fast by latest rMBP standards, but way faster than the original Hitachi at less than 100MB/s R/W speeds.