I certainly agree with you that there is some risk involved, though rocking a dead platform seems to be working pretty well for you! Yet I think Haswell quads like the
Xeon E3-1271v3 linked earlier offer some of the best performance per dollar out there.
I know, I mean the older CPUs are fine, first and second gen i5s are still good today for everything, but as mentioned before, the boards are problem. Just to avoid any misunderstanding, I'm not saying OP should not buy the i5, just to not expect it being very upgrade-able CPU wise, that's all. Otherwise it's a good CPU and mobo for that price and will last long.
As you pointed out, yes my rig is getting old, it's okay for use but if board dies I'm going to have a problem with replacement as well, although my Asrock P67 board has been really rock solid since the day one and as long as this rig works I'm going stick with it. I don't game anymore and for VMs I'm doing and some office stuff it's more than enough.
edit: As much as these platforms are getting old and outdated. I must say that westmere and sandy bridge desktop CPUs were of much higher quality than ivy bridge and newer. If there still would be good new mobos for sale, I would gladly build another 1156 or 1155(SB) system. No delidding, no extensive cooling, no PCB bending, no shit, just turn up the multiplier and/or BCLK and you are good to go for everything.