That's really a decision you need to make yourself, but there is lots of
information out there to read.  Here are a couple of interesting articles:  

http://www.blakkatz.com/vaccination.html

http://www.anc.org/editorials/editorials_article.cfm?identifier=2003_0801_va
ccines

Lauren

________
See my cats:  http://community.webshots.com/album/56955940rWhxAe
Raw Diet Info: http://www.holisticat.com/drjletter.html
http://www.geocities.com/rawfeeders/ForCatsOnly.html
Declawing Info: http://www.wholecat.com/articles/claws.htm

When you go to the appt., ask the vet about the pros & cons of the various
vaccines, & the different forms of some of them, too - there are a bunch of
choices involved.

Make sure the vet knows the habits of all of the cats, besides just the new
inside-only kittens; it'll help for him/her to give you insight as to what
your best choices may be for the various cats involved, & if the other cats
might impact what vaccinations you decide on for the kittens.   A few years
ago I dropped all but really important - to my cats  - vaccines.  They no
longer get the FeLV one, for example, because years & years ago the older
one stopped trying  to escape out the doors whenever I open them, the
younger one turned out to easily adapt to being inside-only, & they have
access to the outside only on a screened-in porch.  So the vets & I decided
that the FeLV vaccine was more risky than it was beneficial to them.  My
late eldest cat - at my vets' suggestions, I'd dropped all vaccines in her
last few years except rabies because she'd become chronically ill & we
didn't want to overload her system anymore than it already was.

AFAIK, the rabies vaccine needs a booster one year after the initial one,
even if you then choose to use the 3 year rabies vaccination schedule
instead of one of the annual rabies vax.  It's been a long time since I had
young cats, but it's possible that other vaccines (the ones you decide to
keep in the regimen) also need a 1 yr. booster even if you vaccinate only
every 3 years after that.

Cathy

--
"Staccato signals of constant information..."
("The Boy in the Bubble")  Paul Simon

Since you are asking for personal opinions, I would do the following:

Since one cat does go out and then back inside, I'd vax all with
FVRCP, since those diseases are the most common and easily spread from
cat to cat.

Aditionally, I would vax the cat that goes out for rabies as well, and
if any other cats come in your yard, FeLV, minimally.

-L.