I have 24 of the MSI 470s and they are my favorites, I actually prefer them over the Sapphire 480/8GB variants which I have as well.
My latest batch of MSI 470s (4GB) have Samsung memory. You didn't take the 1500 strap and copy it up and expect it to clock at 2k on Samsung memory did you?
On my MSI 470s with Samsung VRAM I copied the 1750 strap to the 2000 range and I am running them at 1150/2100 and I am getting 29.3Mh/s out of them rock stable.
Yeah, I am in a very similar boat having good experiences with MSI 470 4GB GPUs. I actually own 15 of them and they've been churning on ETH + DCR for almost 2 months straight with little to no issues, so was very surprised to hear of others having issues with them.
About 10 of mine have Hynix memory and the rest (newer ones) have Samsung. Note that to strap the Samsungs, you actually need to copy the 1750 timings upwards, unlike the Hynix which need the 1500 timings copied. Almost all of my 15 are capable of 2000 or close to it, with the exception of 1 that I usually don't try to push over 1850. So... 1 kinda bad one out of 15 I don't consider bad at all. Hopefully there is not an issue with brand new ones as I have 7 that just arrived this week from Jet & MicroCenter. Luckily I got these for about $160 avg cost/card because now there is a rather bad shortage of these GPUs... hard to find under $230 now... if you can find them at all. Jet is out and MC only available for in-store pickup, but only $185 there so probably worth it if you are close to a store since that seems to be the cheapest available by far anywhere that I've seen.