Argon vs Krypton in triple pane windows

[Big Daddrock]

Am replacing eight double hung windows on front of house. Over years, have already replaced all others with double pane.
Have gotten a good deal on triple panes, but the sales rep is trying to convince me to spend another 10% to get krypton vs argon gas. We will have internal grids (and panes are 1/8" glass). The difference would lower U-factor from 23 to 20. Is it worth the money?

[InfoSponge]

Krypton is better for triple pane - no doubt. I guess your decision might depend on how much the 10% really costs you relative to your utility bills, but the energy efficiency benefit is definitely there with Krypton. It is fairly rare to see triple pane argon windows.

[Big Daddrock]

The krypton will cost an extra $400, vs the $4000 for the eight triple panes. As I said in earlier post, rest of house has double panes. Is the extra money worth it?

[InfoSponge]

Without being an expert in the weather in your area, and the energy performance of the rest of hour home, nobody can promise promise Krypton will "pay back" in X years, but it is definitely a better choice.

You rarely see people get triple pane without Krypton. It just doesn't make that much sense to get high end glass with midrange gas fill (for the small air spaces in triple pane glass). If you are in an area cold enough to get triple pane, I'd almost always suggest Krypton, if the cost isn't going to break you.

If you lived in Southern California, you wouldn't need Krypton, but you wouldn't be considering triple pane either.

[Window4U (IL)]

You shouldn't have to pay any more than about $15 for a krypton upgrade.