Quote Originally Posted by Triskeliongirl View Post
but I know that terry is spec'ing their new Isis sport with a 10 spd 11 or 12/34 casetted by SRAM so it must also be possible for 10 spd.
Huh, it's an IRD cassette, but it still needs a long cage mtb derailleur.

Talk to your LBS and compare the budgets for each. A 30 chainring x 34 cog gives you 23.82 gear inches just a tad lower than a 26 chainring x 28 cog which gives you 25.07.

The chain ring swap is probably cheaper. The risk is you may still want to swap the rear cassette to a 34 someday. A 26 x 34 combo would give you 20.65 which I adore for really, really steep grades but pay the sacrifice of having big jumps in the cassette spacing.