Hi there.
In my opinion, I like Huobi's IEO than Binance's IEO. Right, Binance IEO require the smaller days of holding, but the price of BNB is dumping everyday. But HT isnt, it's price increase everyday, and hard to dump (except BTC dump, all alts will dump). And the Huobi's IEO help us better profit too. From x4-x10 until now, but with Binance's IEO, some IEO is having x0.5-x2 now.
In my opinion, your question is not posed correctly. The main thing here is not the exchange itself, but the project, if the project itself is not very good, then no matter what exchange it will conduct its IEO on, it will not give a lot of profit to investors.