Well I've been enjoying mine (although I didn't get the 2sum). I think I paid $385 for mine (which was a steal) and I see the 2sum as an add-on selling for over $200.
I've rarely shot a DOA gun and had never owned one until the P250. So maybe someone else can give more/better input.
Sig doesn't make a lot of polymer guns. I think there's only the P250, SP2022 (and the other Pro series before it) and the Mosquito. That's pretty much it.
I think the P250 has a really smooth trigger. It has a long pull and it's relatively heavy (which I've found in other DOAs). There is no break that I can feel. The thing feels good in my hand and the controls are within easy usage distance.
I think a lot of it would come down to your tastes. Do you like a safety? The P250 is more like a Glock or M&P than any other Sig I've shot -- and nowhere near a 1911. Do you prefer a more pronounced slide release? This one is much more flush -- again similar to a Glock or M&P. Break down is very simple, but different than other Sigs.
I think so far it's a good value. Look up some YouTube videos and you'll see people plenty happy with them. Durable, Sig Sauer quality, inexpensive, etc. What's not to love?
One other thing. Mine only came with 1 magazine. Not a huge deal, but when you consider they cost about 10% of the overall price of the gun, it's not nothing.
You want to shoot one before you buy? I'd be happy to let you try mine.