2015 13" rMBP for Lightroom and 4K display?

What with all of the experience on this forum, I thought it best to ask you guys, is the current 13" rMBP perfectly capable of running Adobe Ligtroom CC and a 4K Dell monitor?

That's really the most I'm likely to put it through, along with some Airplay movie playback (not at the same time of course).

I'm probably going for 1TB so another few hundred to max out the RAM and CPU are fine, as I'll want to keep it for 5 years

Lot of worried people on other forums, but I tried the 13" in a store a couple of times and have never found a UI lag so I'm cautiously optimistic.