One big drawback is once the novelty has worn off, they will be equivalent to regular poker chips that simply have a decorative bitcoin symbol on them, because that's what they are. What denominates a chip is what the house says it is, so the printed BTC will serve no functional purpose.
Simple printed denominations can be very useful. No need to decide each time what each color will mean, even if your house game has a standard it is easier for new players to not have to ask to make sure they aren't making a mistake or getting ripped off. Plus in this case it 'enforces' the bitcoin standard and keeps it from slipping back into a dollar game which is a risk before everyone is used to needing to bring bitcoins.