Interesting - I'll let you know how I get on.
Please do mate, I'm really interested in the M4.
I have a feeling the firmware update released this week for the MBP's may have fixed any previous issue. People on other apple related forums saying that since the update their SSD performance is noticeably better - and thats across all brands of SSD's not just Crucials.
Bit of mini-bump for this but I have a couple of questions relating to this so I thought I'd post here rather than start a new thread. I've just ordered the 8Gb RAM kit for my 2009 13" MBP and I want to stick an SSD in it at the same time. I was thinking of either the Crucial RealSSD C300 256GB 2.5" or the Crucial RealSSD M4 256GB 2.5". Will either of these do or is there a recommended SSD (250Gb needed) which would be better???
Another couple of questions...
- do I need a cradle or will it fit straight in perfectly?
- do I need to do anything to prep the drive pre/post-install, or can I just install it and then install OSX? (I will be also be using Bootcamp and installing Windows 7).

Could it be just an issue on the 17" macs because of the unshielded SATA cable picking up crosstalk from the power leds?
That's what I thought, so I said that to Crucial and they said there's been compatibility issues across all 3 sizes.
I'm getting rid of my MBP and going to a MBA next summer for when I start my Masters so gonna have to say goodbye to 'fast' SSDs anyway. 
That's what I thought, so I said that to Crucial and they said there's been compatibility issues across all 3 sizes.

Boot time is awesome though!![]()

Agreed, I'm thinking of wrapping the SSD cable with tinfoil to see if that helps.
The cable goes under the drive in mine too!
I might try it anyway, although I hope I'm not tempting fate, I've not had any freezes in the last few hours.
The EFI update switches it off and I haven't bothered reenabling it.
Also, since the EFI update I've noticed a small performance boost but not sure if its the update or switching trim off that's helped.