Wow. Tough one.
Assuming that you can afford either option comfortably AND assuming that both options are within the same estate, same location, same floor, surrounded by the same amenities... yada yada yada, you get the picture.
The BIGGEST difference between a BTO (or an HDB flat for the matter) and a condo is what they are, fundamentally.
An HDB flat will always be priced as affordable housing for the masses. So while you might see some kind of price appreciation (maybe due to a new mall or a new MRT station that's constructed)... don't expect anything massive.
Also, if HDB resale prices look like they're getting out of hand, the government will definitely step in with cooling measures (as they have done so over the years) to manage the prices and keep things affordable.
Condos, on the other hand, aren't subjected to that kind of 'regulation'. Since you're talking about a new-launch condo, you might be able to take advantage of a developer's early bird discount (to my knowledge, that can be as high as 10 per cent sometimes) so the overall price appreciation you get to enjoy for a condo will be pretty decent.
It depends on your objective.
If your primary goal is for investment, then it would be better to go with private property. However, if it's meant for staying-in, then personally, would prefer to go with HDB where you can save the premium for other uses including retirement.