I think that IGH is great for a city bike. Flat repair will require having a wrench, other than that it's not a real problem. 3 speeds create a huge jump between gears, I had a Shimano 8speed for a while, until it broke! Long story short, they had stopped making that model, could not supply the retaining ring that broke, and only suggested I buy a new unit. I did, but I bought a NuVinci N360, and despite the extra pound of weight, they are a much better unit. There is no jump between gears since there are no gears, it continually adjusts whenever you choose whether standing or riding. It is a permanently sealed unit and costs much less than the others on the market.

Marc