Above 2x, you must pay the swap fee and slippage. At 2.5x and 3x leverage, you will have a slight short on the borrowed asset, meaning your equity value will increase when that asset's price falls, and your equity value will decrease when the price rises.If you select a trading pair that didn't contains stablecoin, to maximize your profits, consider borrowing the asset OPPOSITE TO the one you are most bullish about.