Are they safe?

 and which brand is the best for BC9000?

I take it that it's tapehead cleaner you are asking about (the cassette is the housing
for the tape). In short, there are really no bad products, at least none I've seen or
heard about.
I use clean IPA (IsoPropanolAlcohol) that can be bought under many names, such as
f.e. carburettor alcohol which seems to be the cheapest.
Cotton buds are good - first wet to shift the dirt then dry to wipe off the
thin haze left by the IPA.
Avoid using white spirit, it may attack the plastics in some tapeheads.

Martin

Thanks for your reply.

I actually purchased a cleaning tape,

MAXELL AUTOMATIC HEAD CAPSTAIN & ROLLER CLEANER TAPE

for the purpose.

What's your experience with those kind of products? or do you prefer cotton buds for the purpose?

I never liked cleaning tapes and always preferred cotton buds.

The cleaning tapes may be good as a fast solution, especially in hard-to-reach decks (car stereos etc.),
and some are of better quality than others. Maxell sounds like quality to me.
There are some wet-cleaning tapes too, where you put a couple of drops inside the cleaning tape cassette
and let it play in the deck for some time, these may work better.
Still, being a tech guy myself, I prefer the manual way.

It may also be because I've done surgery a couple of times to remove stuck cleaning tapes.

Martin

Agree with Martin - the 9000 is very easy to clean and cleaning tapes can be abrasive. Isopropyl alcohol and cotton buds for me too! I know Tim uses the same.

Well, I guess then I just wasted my money.

RedGrant:

Well, I guess then I just wasted my money.

Do as I - use both methods to overcome the disadvantage of each individually.   I use a wet-type tape head cleaner from discwasher (using their cleaning fluid) followed by a Q-Tip moistened with rubbing (isopropyl) alcohol.