back on topic...
even though you have "good" credit, it's still bad... and here's why:
when you want a loan or need to finance a vehicle etc... they look at 3 things: how long you have carried your debt for... how your repayment schedule is... and what your income to debt ratio is.
the "credit score" is something credit card companies scam you into believing.
i have a "credit score in the mid to high 300's and have no problems at all getting a loan/credit card/financing... and here is why:
I make my payments on time. (keep this VERY IMPORTANT fact in mind... if you are a day late on your payment, it gets reported to the credit bureau as 30 days late. they have 3 slots for late payments 30 days, 60 and 90+ so a day late, is a month late, now reads as a missed payment.)
paying off credit cards as soon as you charge them up is okay, but they also want to see you carry some debt. personal loans and financing from vehicles etc... paying off big chunks of the loan in advance is actually BAD. you need to prove yourself worthy by making your payments for the duration of the loan. paying off the last little bit is okay, but you don't want to get halfway through a 5 year loan and pay off the balance. it will act negatively. they see it as a "windfall" payment. often banks will simply mark the loan as simply repaid. other banks will question the loan. also, don't get a loan to pay another loan... that looks REALLY bad and is, in some places, illegal.
being broke is okay. it shows you are able to handle and control your money. having a fu#$ton of money, but needing a loan doesn't look good. they question whether this person has some sort of gambling addiction or something going on.
the credit bureaus also keep track of who looks into your credit...if a whole bunch of banks and financing companies look into your credit in a short amount of time (say about 2 or 3 months time), you look like you are fishing. that is bad. stay low, you only want to try for new credit twice, maybe 3 times a year MAX. showing disinterest into maxing out your credit load will show you can handle without it. not needing credit, looks REALLY GOOD to creditors. that's when you pounce.
you want to get better credit, it takes time, patience and knowing what they are looking for.