Other than Britax, what are some easy to install convertible car seats? I am a big fan of the Britax ones, but they don't have cupholders and from what I have read of the reviews, the cupholders that you can buy aren't great.

DS1 has a graco car seat and uses the cupholders all of the time but it's a bear to install so I was hoping to get something a little easier to move around for DS2.