2 Questions for car seat tech on booster use:

[Momof2girls]

Is the Graco Ultra Platinum not a good choice for a booster? Is there a way to make sure she is belted in well and not have the slack problem? (5 years/43"/43#)

If the answer is I need a new seat:
I made my choice of a Graco Turbo Booster for my 5 year old dd 43 pound/43". My next question is should I move my 2 1/2 year old dd 26 pound, 35" into the Graco Ultra Platinum that my oldest had or keep her in the Evenflo Triumph (w/ no cup holder!)? The Ultra Platinum is a little newer (made in 2004 I think). The Triumph was made in early 2003. Thanks in advance for your thoughts.

P.S. This car seat makes my 6th seat purchased in the last 5 years (2 kids)!!! But, the Graco Turbo Booster is $40 so it's not too bad. But, if I can use the Platinum Cargos safely I'd like to not buy another seat.

[Joolsplus2]

You can try the Cargo and see how it fits her. Leave the harness in for a test trip, in case you utterly can't stand it as a booster, then you won't have to worry about reinstalling it properly for your younger kiddo. You don't NEED to use the belt guides IF the shoulderbelt fits properly right across your dd's shoulder. If yu DO need the guides, follow the manual...they are technically supposed to stick the belt in it as firmly as a locking clip so that it can't have any slack added to it (thus they aren't really listed in consumer reports "concern" category).

If you are sick of buying seats, you might consider a bigger booster than the Turbo, like the Parkway, which will be much more likely to fit your dd to proper seatbelt age than the Turbo, which is too small for some kids as young as age 7 (of course, there's always handing down, but you know what I'm saying? I have a Turbo and a Parkway and 35 other seats, and we like them both ;)

As for which seat to use for your younger dd...which one do you prefer? If you're in love with the Triumph, keep using it...if you love the harness on the Cargo, then pass it along...does she have a preference? Would sitting lower and not being able to see out the window as well be an issue for her? Either seat is very safe, so use what you both like :)
Julie CPS Tech and mom to 2 in seats
http://www.cpsafety.com/articles/RFAlbum/SarahMA.aspx