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I use whatever is available at the time. All brands seem to work just as well for me. Just remember to use a topcoat like testors decal bonding spray or a coat of dullcoat. Otherwise your decals will end up dissolving when you wet them. Also if you want white lettering you will have to get it done by someone with a printer that can print white, like an Alps printer. An inkjet can't print white.
I have been using a HP 2700 Office Jet Inkjet with very good success. After you have printed your decal use at least two to three light coats of sealer on the decal as opposed to one heavy coat. I use the one shown below and purchased it at HD.