I'm probably the wrong person to be answering this question since the only time I've taken T & P in to the vet was when they needed it. Now I take them in every 6 months because they have "issues" because they are older, but that's another story.
I'm just responding because I think it sounds a little odd myself. Since I have old cats, I don't remember how often you need to take them in as kittens, but I do know that once they have all their booster shots it's only once a year that they really need a checkup. I've never heard of 6 month checkups "because they age so quickly." I know a lot of people here take their kitties in once a year, and I know most vets recommend once a year.
Since Rizzo is just a year old, it might be good to take him in, like you said, just to be sure he's up to date on everything he needs to be, but then in my opinion, once a year is plenty.
Tubby
Spring 1986 - Dec. 11, 2004
RIP Big Boy
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Peanut
Fall 1988 - Jan. 24, 2007
RIP Snotty Girl
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Robin
Fall 1997 - Oct. 6, 2012
RIP Sweet Monkeyhead Girl
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